Method for building core-shell structure quantum dots

Abstract

The present disclosure provides a method for building a core-shell structure quantum dot, which can be applied to the technical fields of nanocomposites and computing materials. The method comprises: inputting a coordinate file of a target molecule corresponding to a target core-shell structure; reading the basis vector of the target molecule and the atomic coordinates of each atom in the target molecule in the coordinate file; determining the center coordinates corresponding to the target core-shell structure by using the basis vector of the target molecule; for the atomic coordinates of each atom in the target molecule, converting the atomic coordinates by using a first preset formula to obtain atomic conversion coordinates; determining the coordinate distance between the atomic conversion coordinates and the center coordinates to obtain a first coordinate distance; in the case where it is determined that the first coordinate distance satisfies a preset condition, determining that the atomic conversion coordinates are target atomic coordinates; writing the target atomic coordinates into a preset file in a preset storage format to obtain a target atomic coordinate set; and building the target core-shell structure according to the target atomic coordinate set.

Description

Technical Field

[0001] This disclosure relates to the fields of nanocomposite materials and computational materials technology, and in particular to a method for constructing core-shell structured quantum dots. Background Technology

[0002] Core-shell nanocomposites are nanocomposites with a core-shell structure consisting of a central particle (core) and a coating layer (shell). Different materials constituting the core-shell structure alter the properties of the composite material. Core-shell nanocomposites exhibit novel characteristics such as excellent magnetic properties, high stability, and high optical activity. Currently, research on core-shell nanocomposites mainly includes metal / inorganic, metal / metal, metal / inorganic, metal / semiconductor, and inorganic / inorganic composites. Compared to single-component nanocomposites, core-shell nanocomposites show promising development prospects in fields such as biomedicine, catalysis, batteries, food, plastics, and environmental protection.

[0003] In related technologies, research on core / shell quantum dots generally requires the preparation of the core / shell structure through chemical experiments, followed by testing and research on its performance.

[0004] In the process of realizing the inventive concept disclosed herein, the inventors discovered at least the following problems in the related technologies: the efficiency of preparing core-shell structures through chemical experiments is slow, and the difficulty of preparing special core-shell structures through chemical experiments is high, thus affecting the research on core-shell structured nanocomposite materials. Summary of the Invention

[0005] To address the aforementioned technical problems, this disclosure provides a method for constructing core-shell quantum dots, thereby at least partially solving at least one of the aforementioned technical problems.

[0006] To solve the above-mentioned technical problems, the technical solution disclosed herein is as follows:

[0007] Input the coordinate file of the target molecule corresponding to the target core-shell structure, wherein the coordinate file includes the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule;

[0008] Read the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule from the coordinate file above;

[0009] The basis vectors of the target molecule are used to determine the center coordinates corresponding to the target core-shell structure.

[0010] For the atomic coordinates of each atom in the target molecule, the atomic coordinates are transformed using a first preset formula to obtain the transformed atomic coordinates;

[0011] Determine the coordinate distance between the aforementioned atomic transformation coordinates and the aforementioned center coordinates to obtain the first coordinate distance;

[0012] If the first coordinate distance meets the preset conditions, the atom transformation coordinates are determined to be the target atom coordinates;

[0013] The target atom coordinates are written to a preset file according to a preset storage format to obtain a set of target atom coordinates; and

[0014] The target core-shell structure is constructed based on the aforementioned set of target atomic coordinates.

[0015] According to embodiments of this disclosure, the above method further includes:

[0016] Input the performance test file, which includes the test type and test parameters;

[0017] The performance of the target core-shell structure was tested according to the test type and test parameters described above.

[0018] According to embodiments of this disclosure, the coordinate file also includes scaling factors;

[0019] The above-mentioned transformation of atomic coordinates using the first preset formula to obtain atomic transformed coordinates includes:

[0020] Given that the atomic coordinates are represented in Cartesian coordinates, the atomic transformation coordinates are obtained by multiplying the atomic coordinates by the scaling factor.

[0021] Given that the atomic coordinates are represented in a fractional coordinate system, the atomic transformation coordinates are obtained by multiplying the atomic coordinates, the scaling factor, and the basis vectors of the target molecule.

[0022] According to embodiments of this disclosure, the preset conditions include a first sub-condition and a second sub-condition, and the target atom coordinates include core target atom coordinates and shell target atom coordinates;

[0023] Under the condition that the first coordinate distance satisfies the preset conditions, the atom transformation coordinates are determined to be the target atom coordinates, and the set of target atom coordinates is obtained, including:

[0024] If the first coordinate distance satisfies the first sub-condition, the atom transformation coordinates are determined to be the nuclear target atom coordinates.

[0025] If the first coordinate distance satisfies the second sub-condition, the atom transformation coordinates are determined to be the shell target atom coordinates.

[0026] The set of target atomic coordinates is obtained based on the above nuclear target atomic coordinates and the above shell target atomic coordinates.

[0027] According to embodiments of this disclosure, the above method further includes:

[0028] A set of stable atomic coordinates is obtained by screening atomic transformation coordinates that meet the preset screening conditions from the atomic transformation coordinates of the above target molecules. The stable atomic coordinates are used to make the outermost atoms of the above target core-shell structure reach a saturated state.

[0029] The construction of the target core-shell structure based on the aforementioned target atom coordinate set includes:

[0030] The target core-shell structure is constructed based on the aforementioned target atom coordinate set and the aforementioned stable atom coordinate set.

[0031] According to embodiments of this disclosure, the preset filtering conditions include a first filtering sub-condition, a second filtering sub-condition, and a third filtering sub-condition;

[0032] The above-mentioned selection of atomic transformation coordinates from the target molecules that meet the preset selection criteria yields a set of stable atomic coordinates, including:

[0033] From the atomic transformation coordinates of the target molecules mentioned above, atomic transformation coordinates that satisfy the first screening condition are selected to obtain a set of candidate stable atomic coordinates.

[0034] From the above set of target atomic coordinates, target atomic coordinates that satisfy the above second screening condition are selected to obtain the filtered target atomic coordinates.

[0035] Based on the target atom coordinates after the above screening, candidate stable atom coordinates that satisfy the third screening condition are selected from the above set of candidate stable atom coordinates to obtain the above set of stable atom coordinates.

[0036] According to embodiments of this disclosure, the process of selecting atomic transformation coordinates from the atomic transformation coordinates of the target molecule that satisfy the first screening condition to obtain a set of candidate stable atomic coordinates includes:

[0037] For the atomic transformation coordinates of each atom in the target molecule, the coordinate distance between the atomic transformation coordinates and the coordinates of each target atom in the target atom coordinate set is determined, thus obtaining the second coordinate distance;

[0038] After determining that the above second coordinate distance is greater than and less than In the case of [the above], the above-mentioned atomic transformation coordinates are determined as the above-mentioned candidate stable atomic coordinates, and the above-mentioned candidate stable atomic coordinate set is obtained;

[0039] The above-mentioned selection of target atom coordinates from the target atom coordinate set that satisfies the second selection condition yields the following selected target atom coordinates:

[0040] Determine the coordinate distance between every two target atom coordinates in the above set of target atom coordinates to obtain the third coordinate distance;

[0041] After determining that the above third coordinate distance is greater than and less than In this case, the two target atom coordinates corresponding to the distance of the third coordinate mentioned above are determined as the filtered target atom coordinates;

[0042] Based on the target atom coordinates selected above, candidate stable atom coordinates that satisfy the third selection condition are selected from the candidate stable atom coordinate set above, resulting in the following stable atom coordinate set:

[0043] For each candidate stable atom coordinate in the above set of candidate stable atom coordinates, the coordinate distance between the above candidate stable atom coordinate and the above-screened target atom coordinate is determined to obtain the fourth coordinate distance;

[0044] After determining that the distance of the fourth coordinate mentioned above is less than In the case of [the above], the above candidate stable atom coordinates are determined as the above stable atom coordinates, and the above set of stable atom coordinates is obtained.

[0045] According to embodiments of this disclosure, the above method further includes:

[0046] For each stable atom coordinate in the above set of stable atom coordinates, if it is determined that the above stable atom coordinate is located on the coordinate axis, the above stable atom coordinate is transformed using the second preset formula to obtain the transformed set of stable atom coordinates;

[0047] The construction of the target core-shell structure based on the target atom coordinate set and the stable atom coordinate set includes:

[0048] The target core-shell structure is constructed based on the target atomic coordinate set and the transformed stable atomic coordinate set.

[0049] According to embodiments of this disclosure, the above method further includes:

[0050] Obtain a preset optimization file, which includes bond length information, elasticity coefficient, bond angle information, fitting parameters, and total energy threshold between different elements;

[0051] The total molecular energy of the target core-shell structure is determined using the above-mentioned bond length information, elastic coefficients, bond angle information, and fitting parameters.

[0052] If the total molecular energy of the target core-shell structure is determined to be greater than the total energy threshold, the target core-shell structure is optimized to obtain the optimized target core-shell structure.

[0053] According to embodiments of this disclosure, the above-mentioned optimization of the target core-shell structure includes:

[0054] Perform the following operations iteratively:

[0055] For the i-th atom in the target core-shell structure, the i-th moving direction and i-th moving distance of the i-th atom are determined based on the bond length information, bond angle information, elastic coefficient and fitting parameters between the i-th atom and its neighboring atoms.

[0056] The atomic coordinates of the i-th atom are updated based on the i-th moving direction and the i-th moving distance, and the relaxed target core-shell structure is finally obtained.

[0057] The total molecular energy of the target core-shell structure after relaxation is determined using the above bond length information, the above elastic coefficient, the above bond angle information, and the above fitting parameters.

[0058] If the total molecular energy of the target core-shell structure after relaxation is determined to be less than the total energy threshold, the iteration is stopped, and the optimized target core-shell structure is obtained.

[0059] According to embodiments of this disclosure, by inputting a coordinate file of the target molecule corresponding to the target core-shell structure, the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule are read from the coordinate file; then, the center coordinates corresponding to the target core-shell structure are determined using the basis vectors of the target molecule; subsequently, for the atomic coordinates of each atom in the target molecule, the atomic coordinates are transformed using a first preset formula to obtain the atomic transformed coordinates; then, the coordinate distance between the atomic transformed coordinates and the center coordinates is determined to obtain a first coordinate distance; if the first coordinate distance satisfies a preset condition, the atomic transformed coordinates are determined to be the target atomic coordinates; then, the target atomic coordinates are written into a preset file according to a preset storage format to obtain a set of target atomic coordinates, and the target core-shell structure is constructed based on the set of target atomic coordinates. The method provided by this disclosure constructs core-shell structure quantum dots through a program, which can conveniently and quickly construct molecular models. This method can also be used to construct special core-shell structures and perform performance testing. It solves the technical problems of slow preparation efficiency due to chemical experiments in preparing core-shell structures and the high difficulty of preparing special core-shell structures through chemical experiments, thus affecting the research on core-shell structure nanocomposites.

[0060] According to embodiments of this disclosure, the molecular model evolves from the original cubic phase to a core-shell structure (spherical phase), with heterojunctions existing between the core and shell layers. This disclosure optimizes the constructed core / shell structure by utilizing the interaction forces, bond lengths, and bond angles between atoms and their surrounding environment, thereby improving the stability of the core-shell structure.

[0061] According to embodiments of this disclosure, first-principles calculations (DFT) require a significant amount of time to converge when relaxing core-shell structures. This disclosure optimizes the core-shell structure through inter-atomic interaction forces, which helps reduce the computational load during first-principles calculations. Attached Figure Description

[0062] Figure 1 A flowchart illustrating a method for constructing core-shell quantum dots according to an embodiment of the present disclosure is shown schematically.

[0063] Figure 2 A flowchart illustrating a construction method according to an embodiment of the present disclosure is shown schematically;

[0064] Figure 3 A flowchart illustrating a stable atom screening method according to an embodiment of the present disclosure is shown schematically;

[0065] Figure 4 The diagram schematically illustrates a pre-optimized core-shell structure constructed according to embodiments of the present disclosure;

[0066] Figure 5 An optimized core-shell structure constructed according to embodiments of the present disclosure is illustrated schematically;

[0067] Figure 6 A schematic diagram illustrating a structural block diagram of a device for constructing core-shell quantum dots according to an embodiment of the present disclosure; and

[0068] Figure 7 A block diagram schematically illustrates an electronic device suitable for implementing a method for constructing core-shell quantum dots according to an embodiment of the present disclosure. Detailed Implementation

[0069] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0070] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0071] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0072] When using expressions such as "at least one of A, B, and C", they should generally be interpreted in accordance with the meaning that is commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B, and C, etc.).

[0073] Core-shell nanocomposites are nanocomposites with a core-shell structure consisting of a central particle (core) and a coating layer (shell). Different materials constituting the core-shell structure alter the properties of the composite material. Core-shell nanocomposites exhibit novel characteristics such as excellent magnetic properties, high stability, and high optical activity. Currently, research on core-shell nanocomposites mainly includes metal / inorganic, metal / metal, metal / inorganic, metal / semiconductor, and inorganic / inorganic composites. Compared to single-component nanocomposites, core-shell nanocomposites show promising development prospects in fields such as biomedicine, catalysis, batteries, food, plastics, and environmental protection.

[0074] In related technologies, research on core / shell quantum dots generally requires the preparation of the core-shell structure through chemical experiments before its properties are tested. However, the efficiency of preparing core-shell structures through chemical experiments is relatively slow, and the preparation of special core-shell structures through chemical experiments is quite difficult, thus affecting the research on core-shell nanocomposites.

[0075] In view of the above, this disclosure provides a method for constructing a core-shell quantum dot structure to address the aforementioned technical problems. The method includes: inputting a coordinate file of a target molecule corresponding to the target core-shell structure, wherein the coordinate file includes the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule; reading the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule from the coordinate file; determining the center coordinates corresponding to the target core-shell structure using the basis vectors of the target molecule; transforming the atomic coordinates of each atom in the target molecule using a first preset formula to obtain atomic transformed coordinates; determining the coordinate distance between the atomic transformed coordinates and the center coordinates to obtain a first coordinate distance; determining the atomic transformed coordinates as target atomic coordinates when the first coordinate distance satisfies a preset condition; writing the target atomic coordinates into a preset file according to a preset storage format to obtain a set of target atomic coordinates; and constructing the target core-shell structure based on the set of target atomic coordinates.

[0076] According to embodiments of this disclosure, by inputting a coordinate file of the target molecule corresponding to the target core-shell structure, the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule are read from the coordinate file; then, the center coordinates corresponding to the target core-shell structure are determined using the basis vectors of the target molecule; subsequently, for the atomic coordinates of each atom in the target molecule, the atomic coordinates are transformed using a first preset formula to obtain the atomic transformed coordinates; then, the coordinate distance between the atomic transformed coordinates and the center coordinates is determined to obtain a first coordinate distance; if the first coordinate distance satisfies a preset condition, the atomic transformed coordinates are determined to be the target atomic coordinates; then, the target atomic coordinates are written into a preset file according to a preset storage format to obtain a set of target atomic coordinates, and the target core-shell structure is constructed based on the set of target atomic coordinates. The method provided by this disclosure constructs core-shell structure quantum dots through a program, which can conveniently and quickly construct molecular models. This method can also be used to construct special core-shell structures and perform performance testing. It solves the technical problems of slow preparation efficiency due to chemical experiments in preparing core-shell structures and the high difficulty of preparing special core-shell structures through chemical experiments, thus affecting the research on core-shell structure nanocomposites.

[0077] Figure 1 A flowchart illustrating a method for constructing core-shell quantum dots according to an embodiment of the present disclosure is shown.

[0078] like Figure 1 As shown, the construction method of this embodiment includes operations S110 to S180.

[0079] In operation S110, input the coordinate file of the target molecule corresponding to the target core-shell structure, wherein the coordinate file includes the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule.

[0080] According to embodiments of this disclosure, the coordinate file can be a coordinate file of the target molecule output by first-principles calculation software, or a coordinate file input by the user.

[0081] According to embodiments of this disclosure, the coordinate file can be a text file with a fixed format. For example, the first line of the coordinate file contains element types, the second line contains scaling factors, the third, fourth, and fifth lines contain basis vectors, the sixth line contains the number of atoms in each element, the seventh line contains the representation of atomic coordinates, and the remaining lines contain atomic coordinates.

[0082] In operation S120, the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule are read from the coordinate file.

[0083] According to embodiments of this disclosure, the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule are read from the coordinate file, and the basis vectors are stored in a basis vector array, and the atomic coordinates of each atom are stored in an atomic coordinate array.

[0084] In operation S130, the basis vectors of the target molecule are used to determine the center coordinates corresponding to the target core-shell structure.

[0085] According to an embodiment of this disclosure, the center coordinates can be determined using formula (1).

[0086]

[0087] Where cer is the center coordinate; a1, a2, a3 are the basis vectors of the target molecule.

[0088] In operation S140, for the atomic coordinates of each atom in the target molecule, the atomic coordinates are transformed using the first preset formula to obtain the atomic transformed coordinates.

[0089] According to embodiments of this disclosure, a first preset formula corresponding to the coordinate system type is determined based on the coordinate system type of the atomic coordinates.

[0090] According to embodiments of this disclosure, the coordinate file further includes a scaling factor; the conversion of the atomic coordinates using the first preset formula to obtain the atomic transformed coordinates includes: when the atomic coordinates are determined to be represented in a Cartesian coordinate system, multiplying the atomic coordinates by the scaling factor to obtain the atomic transformed coordinates; when the atomic coordinates are determined to be represented in a fractional coordinate system, multiplying the atomic coordinates, the scaling factor, and the basis vectors of the target molecule to obtain the atomic transformed coordinates.

[0091] According to an embodiment of this disclosure, when the atomic coordinates are represented in Cartesian coordinates, the first preset formula is formula (2), and the atomic coordinates are transformed using formula (2):

[0092] px(i)=x(i)D(i=1, 2, 3,..., na) (2)

[0093] Where x(i) is the atomic coordinate; px(i) is the atomic transformation coordinate; and D is the scaling factor.

[0094] According to an embodiment of this disclosure, when the atomic coordinates are represented in a fractional coordinate system, the first preset formula is formula (3), and the atomic coordinates are transformed using formula (3):

[0095] px(i)=D·(x1(i)·a1(k)+x2(i)·a2(k)+x3(i)·a3(k)) (i=1, 2, 3,..., na, k=1, 2, 3) (3)

[0096] Where D is the scaling factor; x1(i), x2(i), x3(i) are atomic coordinates; a1, a2, a3 are basis vectors; and px(i) are atomic transformation coordinates.

[0097] In operation S150, the coordinate distance between the above-mentioned atomic transformation coordinates and the above-mentioned center coordinates is determined, and the first coordinate distance is obtained.

[0098] According to embodiments of this disclosure, the coordinate distance dis between the atomic transformation coordinates and the center coordinates can be calculated using formula (4):

[0099]

[0100] Among them, (X) i Y i Z i (X) represents the atomic transformation coordinates, and (X) represents the atomic transformation coordinates. j Y j Z j () is the center coordinate cer.

[0101] In operation S160, if the first coordinate distance meets the preset conditions, the atom transformation coordinates are determined to be the target atom coordinates.

[0102] In operation S170, the target atom coordinates are written into a preset file according to a preset storage format to obtain a set of target atom coordinates.

[0103] According to embodiments of this disclosure, the preset conditions include a first sub-condition and a second sub-condition, and the target atom coordinates include core target atom coordinates and shell target atom coordinates. Determining the atom transformation coordinates as target atom coordinates and obtaining the target atom coordinate set when the first coordinate distance satisfies the preset conditions includes: determining the atom transformation coordinates as core target atom coordinates when the first coordinate distance satisfies the first sub-condition; determining the atom transformation coordinates as shell target atom coordinates when the first coordinate distance satisfies the second sub-condition; and obtaining the target atom coordinate set based on the core target atom coordinates and the shell target atom coordinates.

[0104] According to embodiments of this disclosure, the first sub-condition may include a first coordinate distance that is less than a first input radius.

[0105] According to embodiments of this disclosure, the second sub-condition may include a first coordinate distance that is greater than a first input radius and less than a second input radius, wherein the first input radius is less than the second input radius.

[0106] It should be noted that the first and second input radii can be entered by the user according to their actual needs.

[0107] In operation S180, the target core-shell structure is constructed based on the aforementioned set of target atom coordinates.

[0108] According to embodiments of this disclosure, the method further includes: screening atomic transformation coordinates that meet preset screening conditions from the atomic transformation coordinates of the target molecule to obtain a stable atomic coordinate set, wherein the stable atomic coordinates are atomic transformation coordinates used to make the outermost atoms of the target core-shell structure reach a saturated state, and constructing the target core-shell structure based on the target atomic coordinate set includes: constructing the target core-shell structure based on the target atomic coordinate set and the stable atomic coordinate set.

[0109] According to embodiments of this disclosure, since there may be dangling bonds around the outermost atoms of the target core-shell structure, which are not saturated, stable atoms are used to saturate them in order to ensure the stability of the target core-shell structure.

[0110] According to embodiments of this disclosure, the preset screening conditions include a first screening sub-condition, a second screening sub-condition, and a third screening sub-condition; the process of selecting atomic transformation coordinates that satisfy the preset screening conditions from the atomic transformation coordinates of the target molecule to obtain a set of stable atomic coordinates includes: selecting atomic transformation coordinates that satisfy the first screening sub-condition from the atomic transformation coordinates of the target molecule to obtain a set of candidate stable atomic coordinates; selecting target atomic coordinates that satisfy the second screening sub-condition from the set of target atomic coordinates to obtain screened target atomic coordinates; and selecting candidate stable atomic coordinates that satisfy the third screening sub-condition from the set of candidate stable atomic coordinates based on the screened target atomic coordinates to obtain the set of stable atomic coordinates.

[0111] According to embodiments of this disclosure, the first screening sub-condition may include: the coordinate distance between the atomic transformation coordinates and the target atomic coordinates is greater than... and less than .

[0112] According to embodiments of this disclosure, the second screening sub-condition may include: the coordinate distance between any two target atom coordinates in the target atom coordinate set is greater than 1. and less than .

[0113] According to embodiments of this disclosure, the third screening sub-condition may include: the coordinate distance between the candidate stable atom coordinates and the screened target atom coordinates is less than 1. .

[0114] According to embodiments of this disclosure, the above-mentioned screening of atomic transformation coordinates satisfying the first screening sub-condition from the atomic transformation coordinates of the target molecule to obtain a candidate stable atomic coordinate set includes: for the atomic transformation coordinates of each atom in the target molecule, determining the coordinate distance between the atomic transformation coordinates and each target atom coordinate in the target atomic coordinate set to obtain a second coordinate distance; and determining that the second coordinate distance is greater than... and less than In the case of determining the above-mentioned atomic transformation coordinates as the above-mentioned candidate stable atomic coordinates, the above-mentioned candidate stable atomic coordinate set is obtained; the above-mentioned selection of target atomic coordinates from the above-mentioned target atomic coordinate set that meets the above-mentioned second selection sub-condition to obtain the selected target atomic coordinates includes: determining the coordinate distance between every two target atomic coordinates in the above-mentioned target atomic coordinate set to obtain the third coordinate distance; when the above-mentioned third coordinate distance is greater than and less than In the case of [missing information], the two target atom coordinates corresponding to the aforementioned third coordinate distance are determined as the filtered target atom coordinates; the above-mentioned selection of candidate stable atom coordinates that satisfy the aforementioned third screening sub-condition from the aforementioned candidate stable atom coordinate set based on the aforementioned filtered target atom coordinates, to obtain the aforementioned stable atom coordinate set, includes: for each candidate stable atom coordinate in the aforementioned candidate stable atom coordinate set, determining the coordinate distance between the aforementioned candidate stable atom coordinate and the aforementioned filtered target atom coordinates, to obtain the fourth coordinate distance; when the aforementioned fourth coordinate distance is less than [missing information], ... In the case of [the above], the above candidate stable atom coordinates are determined as the above stable atom coordinates, and the above set of stable atom coordinates is obtained.

[0115] According to an embodiment of this disclosure, the method further includes: for each stable atom coordinate in the set of stable atom coordinates, when it is determined that the stable atom coordinate is located on a coordinate axis, transforming the stable atom coordinate using a second preset formula to obtain a transformed set of stable atom coordinates; wherein, constructing the target core-shell structure based on the target atom coordinate set and the set of stable atom coordinates includes: constructing the target core-shell structure based on the target atom coordinate set and the transformed set of stable atom coordinates.

[0116] According to embodiments of this disclosure, the above method further includes: determining whether any of X, Y, and Z in the atomic coordinates x = (X, Y, Z) is 0; if the condition is met, then the atomic coordinates are transformed using a second preset formula, i.e., formula (5):

[0117]

[0118] Where x(RNN) represents the stable atom coordinates, rx(CNN) represents the target atom coordinates after filtering, and Hatom represents the set of stable atom coordinates after transformation.

[0119] According to embodiments of this disclosure, the converted stable atom coordinates are written into a preset file according to a preset storage format, wherein the preset file may include the following format:

[0120] First line: Number of atoms Atom = Number of atoms in the nucleus (RNc) + Number of atoms in the shell (RNs) + Number of atoms in the hatom;

[0121] Second line: Lattice vector tag: 'LATTICE';

[0122] Third line: First lattice vector: a1;

[0123] Fourth line: Second lattice vector: a2;

[0124] Fifth row: Third lattice vector: a3;

[0125] Line 6: Atom position label: 'POSITION';

[0126] The remaining lines: atomic number, atomic coordinates, 000, in the format: Nel, x1, x2, x3, 0 0 0;

[0127] in,

[0128]

[0129] Where rx(i) are the actual coordinates of the atom, and a1, a2, a3 are the basis vectors.

[0130] According to embodiments of this disclosure, the method further includes: obtaining a preset optimization file, wherein the preset optimization file includes bond length information, elastic coefficient, bond angle information, fitting parameters, and a total energy threshold between different elements; determining the total molecular energy of the target core-shell structure using the bond length information, the elastic coefficient, the bond angle information, and the fitting parameters; and optimizing the target core-shell structure when the total molecular energy of the target core-shell structure is determined to be greater than the total energy threshold, thereby obtaining an optimized target core-shell structure.

[0131] According to embodiments of this disclosure, the preset optimization file may further include the types of elements, which are categorized as elements in a core-shell structure, elements that serve as stable atoms, and the number of elements; the bond length, elastic coefficient, and number of element pairs forming a bond between two elements; the bond angle, fitting parameters, and number of element pairs forming an angle between three elements; the space of size lx, my, and nz generated in the x, y, and z directions; and the maximum number of iteration steps and the total energy convergence criterion (i.e., total energy threshold) for the target molecule iteration.

[0132] According to embodiments of this disclosure, it is determined whether the bond length unit between two elements in a preset optimization file is a Bohr. If it is not a Bohr, the bond length unit needs to be converted to a Bohr.

[0133] According to embodiments of this disclosure, the unit of bond length between two elements Transforming into Bohr, we use the following formula (6):

[0134]

[0135] Where dist1(i) is the unit of The bond length at that time.

[0136] According to embodiments of this disclosure, it is also necessary to include the basis vector units. Transforming it into Bohr, we can use the following formula (7):

[0137]

[0138] Where tau(i) is the transformed basis vector; a(i) is the original basis vector.

[0139] According to embodiments of this disclosure, the atomic coordinates are then updated by converting them to Bohr's basis vectors, using the following formula (8):

[0140] rca(i)=tau(1,i)·x1+tau(2,i)·x2+tau(3,i)·x3(i=1,2,3) (8)

[0141] Where x1, x2, and x3 are the stable atomic coordinates or the target atomic coordinates, rca(i) is the stable atomic coordinates or the target atomic coordinates after transformation using the basis vectors converted to Bohr; tau(1,i), tau(2,i), and tau(3,i) are the transformed basis vectors.

[0142] According to embodiments of this disclosure, the optimization of the target core-shell structure includes iteratively performing the following operations: for the i-th atom in the target core-shell structure, determining the i-th moving direction and the i-th moving distance of the i-th atom based on the bond length information, bond angle information, elastic coefficient, and fitting parameters between the i-th atom and its neighboring atoms; updating the atomic coordinates of the i-th atom based on the i-th moving direction and the i-th moving distance to finally obtain the relaxed target core-shell structure; determining the total molecular energy of the relaxed target core-shell structure using the bond length information, elastic coefficient, bond angle information, and fitting parameters; stopping the iteration when the total molecular energy of the relaxed target core-shell structure is determined to be less than the total energy threshold to obtain the optimized target core-shell structure.

[0143] According to embodiments of this disclosure, determining the i-th moving direction and i-th moving distance of the i-th atom based on the bond length information, bond angle information, elastic coefficient, and fitting parameters between the i-th atom and its neighboring atoms includes: calculating the changes x1, x2, and x3 of the atomic coordinates of the i-th atom in the three directions x, y, and z, which can be obtained by solving the following equation:

[0144] AA(k)·x 3 +BB(k)·x 2 +CC(k)·x+DD(k)=0 (k=1,2,3) where k represents the change of direction, k=1 indicates a change in the x-direction; k=2 indicates a change in the y-direction; and k=3 indicates a change in the z-direction. The elastic constant C... 11 C 12 C 44 The following formula is used for calculation:

[0145]

[0146]

[0147]

[0148] AA=α+β、BB=C 11 CC = C 12 DD=C 44 ;

[0149] α, β, and σ are the elastic coefficients, bond angles, and fitting parameters in step S701, where σ = 0 and d0 is the distance between two atoms.

[0150] Here, we check whether the absolute values ​​of DD(k) and CC(k) are both less than 10. -10 If the conditions are met, then the atomic coordinates remain unchanged; if one of the conditions is not met, then...

[0151]

[0152] Determine if the absolute value of f1 is less than 10 -10 .

[0153] Solving for x k as follows:

[0154]

[0155] According to embodiments of this disclosure, updating the atomic coordinates of the i-th atom based on the i-th moving direction and the i-th moving distance includes: calculating the updated atomic coordinates rca_new(k):

[0156] If the atomic coordinates change in the x-direction, then x2 = 0, x3 = 0; if the atomic coordinates change in the y-direction, then x1 = 0, x3 = 0; if the atomic coordinates change in the z-direction, then x1 = 0, x2 = 0. While maintaining symmetry, the updated atomic coordinates rca_new(k) are calculated using the following formula:

[0157] rca_new(k, i) = rca(k, i) + x k (k=1, 2, 3, i=1, 2, 3,..., 801)

[0158] Here, rca(k, i) are the atomic coordinates after transformation using Bohr's basis vectors.

[0159] According to an embodiment of this disclosure, the determination of the total molecular energy of the relaxed target core-shell structure using the bond length information, the elastic coefficient, the bond angle information, and the fitting parameters includes: determining the total molecular energy of the target core-shell structure using a force field G-VFF model based on the bond length information, the elastic coefficient, the bond angle information, and the fitting parameters.

[0160] According to embodiments of this disclosure, the total molecular energy of the target core-shell structure described above can be determined using the force field G-VFF model using the following formula (9):

[0161]

[0162] in, R i R j R k These are the coordinates of atoms i, j, and k;

[0163] d ij It is the ideal unrelaxed bond distance between atoms of type i and j, i.e., the bond length between atoms i and j;

[0164] It is the ideal unrelaxed bond angle between the jik atom types, where the i atom forms an angle to become the central atom, and j and k are the two end atoms;

[0165] ∑ i It is a summation of all atoms;

[0166] This represents the summation of the nearest neighbors of atom i, indicating how many atoms are bonded or angled with that atom.

[0167] It is the elastic coefficient;

[0168] β jik It is a key corner;

[0169] σ ijk These are the fitting parameters;

[0170] Atom i is the central atom at an angle, while j and k are the atoms at both ends. k > j indicates that repetition should be avoided.

[0171] According to embodiments of this disclosure, the method further includes: after stopping iteration, converting the updated atomic coordinate format.

[0172] According to embodiments of this disclosure, converting the updated atomic coordinate format includes: multiplying the updated atomic coordinates by the new reciprocal lattice vector b to obtain the new atomic coordinates X, which can be determined using formula (10):

[0173]

[0174] Where rca_new(j, i) represents the updated atomic coordinates; b(j, i) represents the new reciprocal lattice vector.

[0175] According to an embodiment of this disclosure, the reciprocal lattice vector b is determined using the following formula (11):

[0176] b(j,i)=a(p(j),p(i))·a(p(p(j)),p(p(i)))-a(p(p(j)),p(i))·a(p(j),p(p(i))) (11)

[0177] Where p = [2, 3, 1], (i, j = 1, 2, 3), and a is the basis vector after unit conversion.

[0178] According to embodiments of this disclosure, the unit cell volume vol is determined using the following formula (12):

[0179]

[0180] Where a is the transformed basis vector; b is the reciprocal lattice vector.

[0181] According to embodiments of this disclosure, the method further includes: determining whether the unit cell volume vol is greater than 0.00000001; if the unit cell volume vol is greater than 0.00000001, then determining the influence factor factor = 1 / vol; if the unit cell volume vol is less than 0.00000001, then the influence factor factor = 1; and obtaining a new reciprocal lattice vector b by multiplying the reciprocal lattice vector b by the influence factor factor.

[0182] According to an embodiment of this disclosure, the obtained new atomic coordinates are written into a preset file.

[0183] According to embodiments of this disclosure, the molecular model is transformed from the original cubic phase to a core / shell structure (spherical phase), with heterojunctions existing between the core and shell layers. This disclosure optimizes the constructed core / shell structure by using the interaction forces, bond lengths, and bond angles between atoms and their surrounding environment, thereby improving the stability of the core / shell structure and making it more consistent with the molecular structure.

[0184] Figure 2 A flowchart illustrating a construction method according to an embodiment of the present disclosure is shown schematically.

[0185] like Figure 2 As shown, the construction method of this embodiment includes operations S201 to S215.

[0186] In operation S201, the basis vectors of the target molecule, the atomic coordinates of each atom in the target molecule, and the scaling factor are read from the coordinate file.

[0187] In operation S202, the basis vectors of the target molecule are used to determine the central coordinates corresponding to the target core-shell structure.

[0188] In operation S203, the atomic coordinates of each atom in the target molecule are transformed to obtain the atomic transformed coordinates.

[0189] In operation S204, the coordinate distance between the atomic transformation coordinates and the center coordinates is determined, and the first coordinate distance is obtained.

[0190] In operation S205, determine whether the distance to the first coordinate is less than or equal to the second input radius. If the distance to the first coordinate is greater than the second input radius, execute operation S215; if the distance to the first coordinate is less than or equal to the second input radius, execute operation S206.

[0191] In operation S206, determine whether the distance to the first coordinate is less than or equal to the first input radius. If the distance to the first coordinate is less than or equal to the first input radius, execute operation S207; if the distance to the first coordinate is greater than the first input radius, execute operation S208.

[0192] In operation S207, the atomic coordinates are determined to be the nuclear target atomic coordinates.

[0193] In operation S208, the atomic coordinates are determined to be the target atomic coordinates of the shell.

[0194] In operation S209, the set of target atom coordinates is obtained based on the nuclear target atom coordinates and the shell target atom coordinates.

[0195] In operation S210, atomic transformation coordinates that meet the preset screening conditions are selected from the atomic transformation coordinates of the target molecule to obtain a set of stable atomic coordinates. The stable atomic coordinates are used to make the outermost atoms of the target core-shell structure reach a saturated state.

[0196] In operation S211, the target core-shell structure is constructed based on the target atom coordinate set and the stable atom coordinate set.

[0197] In operation S212, a preset optimization file is obtained, which includes bond length information, elastic coefficient, bond angle information, fitting parameters, and total energy threshold between different elements.

[0198] In operation S213, the total molecular energy of the target core-shell structure is determined using bond length information, elastic coefficient, bond angle information, and fitting parameters.

[0199] In operation S214, if the total molecular energy of the target core-shell structure is determined to be greater than the total energy threshold, the target core-shell structure is optimized to obtain the optimized target core-shell structure.

[0200] In operation S215, it was determined that the atomic coordinates were not the target atomic coordinates.

[0201] Figure 3 A flowchart illustrating a stable atom screening method according to an embodiment of the present disclosure is shown schematically.

[0202] like Figure 3 As shown, the stable atom screening method in this embodiment includes operations S301 to S312.

[0203] In operation S301, for the atomic transformation coordinates of each atom in the target molecule, the coordinate distance between the atomic transformation coordinates and the coordinates of each target atom in the target atom coordinate set is determined, and the second coordinate distance is obtained.

[0204] In operation S302, determine whether the distance at the second coordinate is greater than [the specified value]. and less than The first filtering sub-condition. If the second coordinate distance meets the first filtering sub-condition, execute operation S303; if the second coordinate distance does not meet the first filtering sub-condition, execute operation S310.

[0205] In operation S303, the atomic transformation coordinates are determined as candidate stable atomic coordinates, and a set of candidate stable atomic coordinates is obtained.

[0206] In operation S304, the coordinate distance between every two target atom coordinates in the target atom coordinate set is determined, and the third coordinate distance is obtained.

[0207] In operation S305, determine whether the distance at the third coordinate is greater than [the specified value]. and less than The second filtering sub-condition. If the third coordinate distance meets the second filtering sub-condition, execute operation S306; if the third coordinate distance does not meet the second filtering sub-condition, execute operation S311.

[0208] In operation S306, the two target atom coordinates corresponding to the distance from the third coordinate are determined as the filtered target atom coordinates.

[0209] In operation S307, for each candidate stable atom coordinate in the set of candidate stable atom coordinates, the coordinate distance between the candidate stable atom coordinate and the selected target atom coordinate is determined, and the fourth coordinate distance is obtained.

[0210] In operation S308, determine whether the distance at the fourth coordinate is less than [the specified value]. The third filtering condition. If the fourth coordinate distance meets the third filtering condition, execute operation S309; ​​if the fourth coordinate distance does not meet the third filtering condition, execute operation S312.

[0211] In operation S309, candidate stable atom coordinates are determined as stable atom coordinates, and a set of stable atom coordinates is obtained.

[0212] During operation S310, it was determined that the atomic transformation coordinates were not candidate stable atomic coordinates.

[0213] In operation S311, it was determined that the two target atom coordinates corresponding to the distance from the third coordinate were not the selected target atom coordinates.

[0214] In operation S312, it was determined that the candidate stable atom coordinates were not stable atom coordinates.

[0215] According to embodiments of this disclosure, the method further includes: inputting a performance test file, wherein the performance test file includes a test type and test parameters; and performing performance testing on the target core-shell structure according to the test type and test parameters.

[0216] According to embodiments of this disclosure, the test types may include magnetic tests, stability tests, optical activity tests, etc.

[0217] The following specific embodiments further illustrate the method for constructing core-shell quantum dots disclosed herein.

[0218] In this embodiment, the target core-shell structure is an InP / ZnS core / shell structure, and the specific process includes the following steps:

[0219] S100: Prepare the input coordinate file for building the core / shell structure.

[0220] In this step, the InP coordinate file is used as the input coordinate file, and it is edited according to the coordinate file format.

[0221] S200: Read and recognize the contents of the input coordinate file.

[0222] In this step, the InP coordinate file content from step S100 is read and stored as: element type (InP), number of atoms of each element (32000-32000), scaling factor (1.0), basis vectors. Coordinate type (C) and atomic coordinates (x).

[0223] S300: Calculates the true coordinates of all atoms and the center coordinates of the core / shell structure.

[0224] In this step, based on the coordinate type (C) and scaling factor (1.0) in step S200, the actual atom coordinates are obtained according to the formula: px = x * D, and stored in the array px. For example, the coordinates of the second atom are (0, 2.981060, 2.981060), and the actual atom coordinates obtained are (0, 2.981060, 2.981060).

[0225] In addition, based on the basis vectors in step S200 and the following formula:

[0226]

[0227] The center coordinates of the core / shell structure constructed in this embodiment are obtained as cer (59.6212, 59.6212, 59.6212).

[0228] S400: Calculate the distance from all atoms in the array px to the center coordinates, and filter out the atoms of the core and shell in the core / shell structure.

[0229] In this step, the distances from all atoms in the array `px` to the center coordinate `cer` are calculated. For example, if the actual coordinates of the second atom are (0, 2.981060, 2.981060) and the center coordinates are (59.6212, 59.6212, 59.6212), then the distance between this atom and the center coordinates is:

[0230]

[0231] After calculating the distances from all atoms in the array px to the center coordinate cer, atoms in the core-shell structure are filtered based on the first and second input radii. For example, the first input radius... Second input radius The distance from the second atom to the center coordinate is greater than Therefore, the second atom is not in the core / shell structure. This process is repeated for each atom in the array `px` to filter out atoms in the core / shell structure. Ultimately, the number of atoms in the core of the core / shell structure is determined to be 159, and the number of atoms in the shell is 366. These 525 atoms are stored in the array `rx`, forming the atoms of the core / shell structure.

[0232] S500: Select atoms that meet the criteria as fractional H atoms (i.e. stable atoms) and change their coordinates.

[0233] In this step, the outermost shell atoms may have dangling bonds and are not yet saturated. For the stability of the core / shell structure, fractional H atoms are saturated with them. The spacing between each pair of atoms in array rx in step S400 and array px in S300 is calculated. For spacing greater than... And less than The atomic coordinates are filtered, and the matching atoms are stored in array NN. The atomic order of some atoms in NN is listed through calculation, for example (35995, 35996, 35997, 35998, 35978, 35980, ...). Then, the distance between each pair of atomic coordinates in array rx from step S400 is calculated. For distances greater than... And less than The atomic coordinates are filtered and placed into the CNN array; then the spacing between the atoms in the NN array and the CNN array is calculated, and atoms with a spacing less than 1 are selected. The atoms are stored in the array RNN. The atomic order of some atoms in the RNN is enumerated through calculation, for example (84, 85, 86, 87, 341, 354, 102, ...). For each atom in the RNN array, it is determined whether any of the X, Y, or Z coordinates in the atom's coordinate x = (X, Y, Z) is 0. If the condition is met, the coordinates of that atom are transformed, and the new coordinates are stored in the array Hatom.

[0234] S600: Writes the atomic coordinates in array rx and array Hatom to a preset file to build an InP / ZnS core / shell structure.

[0235] The default file is, for example, the "atom.config" file. The format of the "atom.config" file is as follows:

[0236] First line: Number of atoms: 801 = 79 (In atoms) + 80 (P atoms) + 170 (Zn atoms) + 196 (S atoms) + 276 (H atoms)

[0237] Second line: Lattice vector tag: 'LATTICE'

[0238] Third, Fourth, and Fifth Elements: Base Vector

[0239] Line 6: Atom position label: 'POSITION'

[0240] The remaining lines: atomic number, atomic coordinates: Nel,

[0241] In a core / shell structure, the atomic number of 'In' is defined as 49, and the atomic number of 'P' is defined as 15. The atomic coordinates in array rx are converted to fractional coordinates, and each atomic coordinate is appended with '0 0 0' sequentially, for example:

[0242]

[0243] In the shell of the core / shell structure, the atomic number of element 'In' is defined as 30, and the atomic number of element 'P' is defined as 16. The atomic coordinates in array rx are converted to fractional coordinates, and '0 0 0' is added to the end of each atomic coordinate sequentially, for example:

[0244]

[0245] In the array Hatom, atoms belonging to the core / shell structure are defined with atomic numbers of 118, and atoms outside this range are defined with atomic numbers of 112. Atomic coordinates are converted to fractional coordinates, and each atomic coordinate is appended with '00 0' sequentially, for example:

[0246]

[0247] In the above atomic numbers, the atomic number of 'In' is 49, the atomic number of 'P' is 15, the atomic number of 'Zn' is defined as 30, and the atomic number of 'S' is defined as 16.

[0248] S700: Optimizes the existing InP / ZnS core / shell structure.

[0249] In this step, a preset optimization file, such as the database file "vff.data", is read to obtain the bond lengths, bond angles and total energies between different atoms in the file. All atoms are scanned one by one, and the atomic position of each atom is relaxed. The optimized core / shell structure has smaller bond lengths between atoms, resulting in less computation in first-principles calculations.

[0250] S701: Read the database file "vff.data".

[0251] In this step, the following arrays are read: element type (ntype = 6), bond type (npair = 8), angle type (nangle = 24); atomic number (atyp), element type (2.8 1.8), for example: 49 2.8; 118 1.8, where 49 represents In atoms in a core-shell structure, and 118 represents fractional H atoms outside the core-shell structure; small grids in the x, y, and z directions (lx = 1, my = 1, nz = 1); bond length (dist(A)) and elasticity coefficient (alfa1) between two atoms, for example: 49 152.5830 27.7837, indicating that the bond length between atom with atomic number 49 and atom with atomic number 15 is 2.5830, and the elasticity coefficient is 27.7837; angle type (betal) and fitting parameter (gamma1) between three atoms, for example: 49 15 497.27354-0.3333333333 indicates that the bond angle between the atom with atomic number 49 and the atom with atomic number 15 is 7.27354, the fitting parameter is -0.3333333333; and the maximum number of iterations, niter = 40000, and the standard energy of convergence, Etol(eV) = 10. -8 .

[0252] Additionally, the unit of the bond length distl needs to be changed. Transform into Bohr.

[0253] S702: Set the basis vector unit Transform into Bohr.

[0254] In this step, the basis vector of the "atom.config" file obtained in step S600 is...

[0255]

[0256] Transforming into Bohr, the formula is:

[0257]

[0258] The transformed basis vectors are:

[0259]

[0260] Then, the atomic coordinates rca in the array px are updated using the transformed basis vectors, which can be achieved using the following formula:

[0261] rca(k)=tau(1,k)·x1+tau(2,k)·x2+tau(3,k)·x3(k=1,2,3)

[0262] S703: Calculate the total energy Etot of a core / shell molecule.

[0263] To calculate the positions of relaxed atoms within the supercell, the force field G-VFF model was used. The total G-VFF energy can be expressed as:

[0264]

[0265] in, R i R j R k These are the coordinates of atoms i, j, and k. It is the ideal unrelaxed bond distance between atomic types i and j, i.e., distl. It is the ideal unrelaxed bond angle between the JIK atom types; This represents the summation over the nearest neighbors of atom i; elasticity coefficients, bond angles, and fitting parameters. β jik =beta, σ ijk =gamma1. Then compare Etot_old with Etot = E VFF The absolute value of the difference is used to determine whether the total energy of this iteration is less than the value of Etol in step S701 compared to the total energy of the previous iteration. If the condition is not met, the value of Etot is assigned to Etot_old, and the loop continues. If the condition is met, relaxation is complete, and the atomic position Ri = rca_new(i) is the updated atomic coordinate.

[0266] S704: Calculate the changes in atomic coordinates x1, x2, and x3 of each atom in the three directions x, y, and z;

[0267] Firstly, obtain x by solving the equation. i :

[0268] AA(k)·x 3 +BB(k)·x 2 +CC(k)·x+DD(k)=0(k=1,2,3)

[0269] k represents the direction of change; k=1 indicates a change in the x-direction; k=2 indicates a change in the y-direction; and k=3 indicates a change in the z-direction. The elastic constant C... 11 C 12 C 44 The following formula is used for calculation:

[0270]

[0271]

[0272]

[0273] AA = α + β, BB = C 11 , CC = C 12 , DD = C 44 ;

[0274] α, β, and σ are the elastic coefficient, bond angle, and fitting parameter in step S701. Here, σ = 0, and d0 is the distance between two atoms.

[0275] Here, it is judged whether the absolute values of DD(k) and CC(k) are both less than 10 -10 , if the condition is met, the atomic coordinates remain unchanged; if one of them does not meet the condition, then

[0276]

[0277] judge whether the absolute value of f1 is less than 10 -10 . <​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0287] Then, using the formula: b = b·factor, we obtain the new reciprocal lattice vector:

[0288]

[0289] Multiply the updated atomic coordinates rca_new(k) obtained in step S705 by the new reciprocal lattice vector b to obtain the final atomic coordinates X, as shown in the formula:

[0290]

[0291] S800: Writes the final atom coordinates to the preset file "xatom.out".

[0292] The difference between the atomic coordinate information in the optimized "xatom.out" file and the "atom.config" file in S600 is the change in the specific atomic coordinates.

[0293] The “xatom.out” file format is as follows:

[0294] First line: Number of atoms natms = Atom = 801

[0295] Second line: Lattice vector tag: 'LATTICE'

[0296] Third, Fourth, and Fifth Elements: Base Vector

[0297] Line 6: Atom position label: 'POSITION'

[0298] The remaining lines: atomic number, atomic coordinates, 0 0 0: Nel, X1, X2, X3, 0 0 0

[0299] For example, it is the same atom as the one listed in step S600:

[0300]

[0301] Figure 4 The diagram schematically illustrates a pre-optimized core-shell structure constructed according to embodiments of the present disclosure.

[0302] Figure 5 An optimized core-shell structure constructed according to an embodiment of the present disclosure is illustrated schematically.

[0303] like Figure 4 and Figure 5 As shown, through comparison Figure 4 and Figure 5It can be observed that the diameter of the core / shell structure decreases, and the bond lengths between atoms become shorter. For example, the bond lengths between atoms in the unoptimized InP / ZnS core / shell molecular model are: ; The bond lengths between atoms in the optimized InP / ZnS core / shell molecular model are: .

[0304] It should be noted that, unless it is explicitly stated that there is a sequential order of execution between different operations, or that there is a sequential order of execution between different operations in terms of technical implementation, the execution order between multiple operations may not be significant, and multiple operations may be executed simultaneously.

[0305] Based on the above-described method for constructing core-shell quantum dots, this disclosure also provides a device for constructing core-shell quantum dots. The following will be combined with... Figure 6 The device is described in detail.

[0306] Figure 6 A schematic block diagram of a device for constructing core-shell quantum dots according to an embodiment of the present disclosure is shown.

[0307] like Figure 6 As shown, the core-shell quantum dot construction device 600 of this embodiment includes an input module 610, a reading module 620, a first determining module 630, a conversion module 640, a second determining module 650, a third determining module 660, a writing module 670, and a construction module 680.

[0308] The input module 610 is used to input a coordinate file of the target molecule corresponding to the target core-shell structure, wherein the coordinate file includes the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule. In one embodiment, the input module 610 can be used to perform the operation S110 described above, which will not be repeated here.

[0309] The reading module 620 is used to read the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule from the coordinate file. In one embodiment, the reading module 620 can be used to perform the operation S120 described above, which will not be repeated here.

[0310] The first determining module 630 is used to determine the center coordinates corresponding to the target core-shell structure using the basis vectors of the target molecule. In one embodiment, the first determining module 630 can be used to perform the operation S130 described above, which will not be repeated here.

[0311] The conversion module 640 is used to convert the atomic coordinates of each atom in the target molecule using a first preset formula to obtain the atomic converted coordinates. In one embodiment, the conversion module 640 can be used to perform the operation S140 described above, which will not be repeated here.

[0312] The second determining module 650 is used to determine the coordinate distance between the atomic transformation coordinates and the center coordinates to obtain a first coordinate distance. In one embodiment, the second determining module 650 can be used to perform the operation S150 described above, which will not be repeated here.

[0313] The third determining module 660 is used to determine the atom transformation coordinates as target atom coordinates when the first coordinate distance satisfies a preset condition. In one embodiment, the third determining module 660 can be used to perform the operation S160 described above, which will not be repeated here.

[0314] The writing module 670 is used to write the target atom coordinates into a preset file according to a preset storage format, thereby obtaining a set of target atom coordinates. In one embodiment, the writing module 670 can be used to perform the operation S170 described above, which will not be repeated here.

[0315] The construction module 680 is used to construct the target core-shell structure based on the aforementioned set of target atom coordinates. In one embodiment, the construction module 680 can be used to perform the operation S180 described above, which will not be repeated here.

[0316] Any one or more of the modules, submodules, units, and subunits according to embodiments of this disclosure, or at least part of the functions of any one or more of them, can be implemented in one module. Any one or more of the modules, submodules, units, and subunits according to embodiments of this disclosure can be implemented by dividing them into multiple modules. Any one or more of the modules, submodules, units, and subunits according to embodiments of this disclosure can be at least partially implemented as hardware circuitry, such as Field Programmable Gate Arrays (FPGAs), Programmable Logic Arrays (PLAs), Systems-on-Chip, Systems-on-Substrate, Systems-on-Package, Application-Specific Integrated Circuits (ASICs), or implemented in hardware or firmware by any other reasonable means of integrating or packaging circuitry, or implemented in software, hardware, or firmware, or in any suitable combination of any of these three implementation methods. Alternatively, one or more of the modules, submodules, units, and subunits according to embodiments of this disclosure can be at least partially implemented as computer program modules, which, when run, can perform corresponding functions.

[0317] According to embodiments of this disclosure, any and multiple modules selected from the input module 610, reading module 620, first determining module 630, conversion module 640, second determining module 650, third determining module 660, writing module 670, and building module 680 can be combined into a single module, or any one of these modules can be split into multiple modules. Alternatively, at least some of the functionality of one or more of these modules can be combined with at least some of the functionality of other modules and implemented in a single module. According to embodiments of this disclosure, at least one of the input module 610, read module 620, first determination module 630, conversion module 640, second determination module 650, third determination module 660, write module 670, and build module 680 can be at least partially implemented as hardware circuits, such as field-programmable gate arrays (FPGAs), programmable logic arrays (PLAs), systems-on-a-chip, systems-on-a-substrate, systems-on-package, application-specific integrated circuits (ASICs), or any other reasonable means of integrating or packaging circuits, or implemented in software, hardware, or firmware, or in any suitable combination of any of these three implementation methods. Alternatively, at least one of the input module 610, read module 620, first determination module 630, conversion module 640, second determination module 650, third determination module 660, write module 670, and build module 680 can be at least partially implemented as a computer program module, which, when run, can perform corresponding functions.

[0318] It should be noted that the apparatus for constructing core-shell quantum dots in the embodiments of this disclosure corresponds to the method for constructing core-shell quantum dots in the embodiments of this disclosure. For a detailed description of the apparatus for constructing core-shell quantum dots, please refer to the method for constructing core-shell quantum dots, which will not be repeated here.

[0319] Figure 7 A block diagram schematically illustrates an electronic device suitable for implementing a method for constructing core-shell quantum dots according to an embodiment of the present disclosure.

[0320] like Figure 7As shown, an electronic device 700 according to an embodiment of the present disclosure includes a processor 701, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 702 or a program loaded from a storage portion 708 into a random access memory (RAM) 703. The processor 701 may include, for example, a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or an associated chipset and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 701 may also include onboard memory for caching purposes. The processor 701 may include a single processing unit or multiple processing units for performing different actions of the method flow according to an embodiment of the present disclosure.

[0321] RAM 703 stores various programs and data required for the operation of electronic device 700. Processor 701, ROM 702, and RAM 703 are interconnected via bus 704. Processor 701 performs various operations of the method flow according to embodiments of the present disclosure by executing programs in ROM 702 and / or RAM 703. It should be noted that the programs may also be stored in one or more memories other than ROM 702 and RAM 703. Processor 701 may also perform various operations of the method flow according to embodiments of the present disclosure by executing programs stored in said one or more memories.

[0322] According to embodiments of this disclosure, the electronic device 700 may further include an input / output (I / O) interface 705, which is also connected to a bus 704. The electronic device 700 may also include one or more of the following components connected to the I / O interface 705: an input section 706 including a keyboard, mouse, etc.; an output section 707 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 708 including a hard disk, etc.; and a communication section 709 including a network interface card such as a LAN card, modem, etc. The communication section 709 performs communication processing via a network such as the Internet. A drive 710 is also connected to the I / O interface 705 as needed. A removable medium 711, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on the drive 710 as needed so that computer programs read from it can be installed into the storage section 708 as needed.

[0323] This disclosure also provides a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiments; or it may exist independently and not assembled into the device / apparatus / system. The computer-readable storage medium carries one or more programs that, when executed, implement the method according to the embodiments of this disclosure.

[0324] According to embodiments of this disclosure, the computer-readable storage medium may be a non-volatile computer-readable storage medium, such as, but not limited to: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this disclosure, the computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. For example, according to embodiments of this disclosure, the computer-readable storage medium may include ROM 702 and / or RAM 703 and / or one or more memories other than ROM 702 and RAM 703 described above.

[0325] Embodiments of this disclosure also include a computer program product comprising a computer program containing program code for performing the methods shown in the flowchart. When the computer program product is run on a computer system, the program code enables the computer system to implement the method for constructing core-shell quantum dots provided in the embodiments of this disclosure.

[0326] When the computer program is executed by the processor 701, it performs the functions defined in the system / apparatus of this disclosure embodiments. According to embodiments of this disclosure, the systems, apparatuses, modules, units, etc., described above can be implemented by computer program modules.

[0327] In one embodiment, the computer program may rely on a tangible storage medium such as an optical storage device or a magnetic storage device. In another embodiment, the computer program may also be transmitted and distributed in the form of signals over a network medium, and may be downloaded and installed via the communication section 709, and / or installed from a removable medium 711. The program code contained in the computer program can be transmitted using any suitable network medium, including but not limited to: wireless, wired, etc., or any suitable combination thereof.

[0328] In such an embodiment, the computer program can be downloaded and installed from a network via the communication section 709, and / or installed from the removable medium 711. When the computer program is executed by the processor 701, it performs the functions defined in the system of this disclosure embodiment. According to embodiments of this disclosure, the systems, devices, apparatuses, modules, units, etc., described above can be implemented by computer program modules.

[0329] According to embodiments of this disclosure, program code for executing the computer programs provided in embodiments of this disclosure can be written in any combination of one or more programming languages. Specifically, these computational programs can be implemented using high-level procedural and / or object-oriented programming languages, and / or assembly / machine languages. Programming languages ​​include, but are not limited to, languages ​​such as Java, C++, Python, "C", or similar programming languages. The program code can execute entirely on the user's computing device, partially on the user's device, partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0330] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0331] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in this disclosure. In particular, the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or combinations fall within the scope of this disclosure.

[0332] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

[0333] The specific embodiments described above further illustrate the purpose, technical solutions, and beneficial effects of this disclosure. It should be understood that the above descriptions are merely specific embodiments of this disclosure and are not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A method for constructing core-shell quantum dots, comprising: Input a coordinate file of the target molecule corresponding to the target core-shell structure, wherein the coordinate file includes the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule; Read the basis vectors of the target molecule and the atomic coordinates of each atom in the target molecule from the coordinate file; The center coordinates corresponding to the target core-shell structure are determined using the basis vectors of the target molecule; For the atomic coordinates of each atom in the target molecule, the atomic coordinates are transformed using a first preset formula to obtain the transformed atomic coordinates; Determine the coordinate distance between the atomic transformation coordinates and the center coordinates to obtain the first coordinate distance; If the first coordinate distance meets the preset conditions, the atomic transformation coordinates are determined to be the target atomic coordinates; The target atom coordinates are written into a preset file according to a preset storage format to obtain a set of target atom coordinates; and The target core-shell structure is constructed based on the target atom coordinate set; The method further includes: A set of stable atomic coordinates is obtained by screening atomic transformation coordinates that meet preset screening conditions from the atomic transformation coordinates of the target molecule. The stable atomic coordinates are used to make the outermost atoms of the target core-shell structure reach a saturated state. The construction of the target core-shell structure based on the target atom coordinate set includes: The target core-shell structure is constructed based on the target atom coordinate set and the stable atom coordinate set; The preset conditions include a first sub-condition and a second sub-condition, and the target atom coordinates include the core target atom coordinates and the shell target atom coordinates; The step of determining the atom transformation coordinates as target atom coordinates and obtaining the target atom coordinate set when the first coordinate distance meets the preset conditions includes: If the first coordinate distance satisfies the first sub-condition, the atomic transformation coordinates are determined to be the nuclear target atomic coordinates; If the first coordinate distance satisfies the second sub-condition, the atom transformation coordinates are determined to be the shell target atom coordinates; The target atom coordinate set is obtained based on the core target atom coordinates and the shell target atom coordinates.

2. The method according to claim 1, further comprising: Input a performance test file, wherein the performance test file includes test type and test parameters; The target core-shell structure is subjected to performance testing according to the test type and the test parameters.

3. The method according to claim 1, wherein, The coordinate file also includes scaling factors; The process of transforming the atomic coordinates using a first preset formula to obtain the transformed atomic coordinates includes: Given that the atomic coordinates are represented in Cartesian coordinates, the atomic transformation coordinates are obtained by multiplying the atomic coordinates by the scaling factor. Given that the atomic coordinates are represented in a fractional coordinate system, the atomic transformation coordinates are obtained by multiplying the atomic coordinates, the scaling factor, and the basis vectors of the target molecule.

4. The method according to claim 1, wherein, The preset filtering conditions include a first filtering sub-condition, a second filtering sub-condition, and a third filtering sub-condition; The step of selecting atomic transformation coordinates that meet preset selection conditions from the atomic transformation coordinates of the target molecule to obtain a stable set of atomic coordinates includes: A set of candidate stable atomic coordinates is obtained by filtering atomic transformation coordinates that satisfy the first screening condition from the atomic transformation coordinates of the target molecule. From the set of target atomic coordinates, target atomic coordinates that satisfy the second filtering sub-condition are selected to obtain the filtered target atomic coordinates; Based on the target atom coordinates after screening, candidate stable atom coordinates that satisfy the third screening condition are selected from the candidate stable atom coordinate set to obtain the stable atom coordinate set.

5. The method according to claim 4, wherein, The step of selecting atomic transformation coordinates from the atomic transformation coordinates of the target molecule that satisfy the first screening condition to obtain a set of candidate stable atomic coordinates includes: For each atom in the target molecule, the coordinate distance between the atomic transformation coordinates and the coordinates of each target atom in the target atom coordinate set is determined to obtain the second coordinate distance; The distance to the second coordinate is determined to be greater than 0.

1. And less than 2.6 In the case of [the specific situation], the atomic transformation coordinates are determined as the candidate stable atomic coordinates, and the set of candidate stable atomic coordinates is obtained; The step of filtering target atomic coordinates from the set of target atomic coordinates that satisfy the second filtering sub-condition to obtain the filtered target atomic coordinates includes: Determine the coordinate distance between every two target atom coordinates in the target atom coordinate set to obtain the third coordinate distance; The distance to the third coordinate is determined to be greater than 0.

1. And less than 2.6 In the case of [the third coordinate distance], the two target atom coordinates corresponding to the distance to the third coordinate are determined as the filtered target atom coordinates; The step of selecting candidate stable atomic coordinates from the set of candidate stable atomic coordinates that satisfy the third screening condition based on the selected target atomic coordinates to obtain the set of stable atomic coordinates includes: For each candidate stable atom coordinate in the set of candidate stable atom coordinates, the coordinate distance between the candidate stable atom coordinate and the screened target atom coordinate is determined to obtain the fourth coordinate distance; The distance to the fourth coordinate is determined to be less than 0.

1. In the case of [the situation], the candidate stable atom coordinates are determined as the stable atom coordinates, and the set of stable atom coordinates is obtained.

6. The method according to claim 1, further comprising: For each stable atom coordinate in the set of stable atom coordinates, if it is determined that the stable atom coordinate is located on the coordinate axis, the stable atom coordinate is transformed using a second preset formula to obtain the transformed set of stable atom coordinates. The step of constructing the target core-shell structure based on the target atom coordinate set and the stable atom coordinate set includes: The target core-shell structure is constructed based on the target atomic coordinate set and the transformed stable atomic coordinate set.

7. The method according to claim 1, further comprising: Obtain a preset optimization file, wherein the preset optimization file includes bond length information, elastic coefficient, bond angle information, fitting parameters and total energy threshold between different elements; The total molecular energy of the target core-shell structure is determined using the bond length information, the elastic coefficient, the bond angle information, and the fitting parameters. If the total molecular energy of the target core-shell structure is determined to be greater than the total energy threshold, the target core-shell structure is optimized to obtain the optimized target core-shell structure.

8. The method according to claim 7, wherein, The optimization of the target core-shell structure includes: Perform the following operations iteratively: For the i-th atom in the target core-shell structure, the i-th moving direction and i-th moving distance of the i-th atom are determined based on the bond length information, the bond angle information, the elastic coefficient and the fitting parameters between the i-th atom and its neighboring atoms; The atomic coordinates of the i-th atom are updated according to the i-th moving direction and the i-th moving distance, and the relaxed target core-shell structure is finally obtained. The total molecular energy of the relaxed target core-shell structure is determined using the bond length information, the elastic coefficient, the bond angle information, and the fitting parameters. If the total molecular energy of the relaxed target core-shell structure is determined to be less than the total energy threshold, the iteration is stopped, and the optimized target core-shell structure is obtained.

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