A modeling method for functionalization of ultrafine diamond nanowires

Abstract

The application discloses a modeling method for functionalization of superfine diamond nanowires, comprising the following steps: establishing a functional group molecular model, calculating a functional group space coordinate transformation parameter equation; establishing a periodic cell model of the superfine diamond nanowires; establishing a superfine diamond nanowire model and transforming atom coordinates of the superfine diamond nanowire model to an origin; selecting a functionalized region on the superfine diamond nanowire model, selecting a random functionalized site through a random number and excluding adjacent functionalized sites; calculating a coordinate conversion matrix based on the functionalized site to obtain corresponding functional group molecular coordinates; and integrating topological information of the functionalized superfine diamond nanowire model. The application realizes accurate positioning and control of the functional groups on the surface of the diamond nanowires, is helpful to quantitative research on the performance of one-dimensional nanomaterials by the functional groups and the performance of modified materials by the functionalized one-dimensional nanomaterials, and analyzes the internal mechanism at a microscale.

Description

Technical Field

[0001] This invention relates to the field of low-dimensional nanomaterial modeling and atomic-scale simulation, specifically to a modeling method for functionalizing ultrafine diamond nanothreads. Background Technology

[0002] Low-dimensional nanomaterials, especially carbon nanomaterials, have shown great application potential in microelectronics, aerospace, civil engineering, and defense due to their unique structure and excellent physicochemical properties. Nanowires, as an important one-dimensional nanomaterial, are not only crucial building blocks of advanced nanodevices but can also serve as additive phases to significantly enhance or modulate the properties of traditional materials, such as mechanical, thermal, and electrical conductivity. Functionalization is a commonly used modification strategy to further improve the performance of one-dimensional nanomaterials or to leverage their superior properties as additive phases. For applications involving nano-additive phases, functionalized one-dimensional nanomaterials can effectively avoid aggregation caused by surface effects, while simultaneously strengthening the interfacial strength with the matrix material or reducing interfacial thermal resistance, thereby better utilizing the performance of the nano-additive phase.

[0003] Currently, researchers have introduced various functional groups into one-dimensional nanomaterials, such as methyl (-CH3), ethyl (-C2H5), and phenyl (-C6H5). However, due to the randomness of functional group positions and variations in functionalization among different one-dimensional nanomaterials during experiments, it is difficult to conduct quantitative research on the impact of functional groups on the properties of one-dimensional nanomaterials, and on the effects of functionalized one-dimensional nanomaterials on the properties of modified materials. Atomic-scale simulations, starting from nanoscale models, can effectively compensate for this deficiency and elucidate the intrinsic mechanisms at the microscale. The primary challenge of atomic-scale simulations is the controllable modeling of one-dimensional nanomaterials. Although some atomic-scale simulations have explored the properties of functionalized one-dimensional nanomaterials, the selection of functional group sites in different studies is usually manual and random, making it difficult to standardize comparisons and explore the influence of functional groups. Therefore, it is essential to establish a standardized, controllable modeling method for the functionalization of one-dimensional nanomaterials. Summary of the Invention

[0004] To address the lack of controllable modeling methods for the functionalization of existing one-dimensional carbon nanomaterials, this invention provides a modeling method for the functionalization of ultrafine diamond nanowires, the specific technical solution of which is as follows:

[0005] A modeling method for functionalizing ultrafine diamond nanowires includes the following steps:

[0006] S1: Establish a functional group molecular model, and establish spatial coordinate transformation parameter equations for rotation matrix, translation matrix, and orientation factor based on the coordinates of the functional group model;

[0007] S2: Establish a periodic unit cell model of ultrafine diamond nanowires, and number the carbon and hydrogen atoms in the unit cell model in a clockwise direction;

[0008] S3: Based on the principal coordinate direction of the periodic unit cell model of the ultrafine diamond nanowire, the length of the diamond nanowire is preset, an ultrafine diamond nanowire model of the required length is established, and the carbon and hydrogen atom coordinates of the ultrafine diamond nanowire model are placed into two arrays respectively; then the bottom center of the ultrafine diamond nanowire model is transformed to the origin of the coordinate system, and the length direction is along the principal coordinate direction of the coordinate system.

[0009] S4: Based on the carbon atom coordinates converted from the ultrafine diamond nanowire model, the site regions and proportions of functional groups to be added are set, while unreasonable functional group addition sites are eliminated. Finally, all carbon atom coordinates and hydrogen atom coordinates of the ultrafine diamond nanowire model are integrated to obtain the topological information of the overall functionalized model.

[0010] Further, step S4 includes:

[0011] S41: Select a pseudo-functionalized region according to the simulation requirements; store the carbon and hydrogen atom coordinates of the pseudo-functionalized region into the functionalized region carbon atom array and the corresponding hydrogen atom array;

[0012] S42: Calculate the total number of functional groups to be added based on the functionalization ratio and the total number of carbon atoms in the functionalizable region.

[0013] S43: Control the random number seed. Based on the array of carbon atoms in the functionalizable region, obtain a random number and extract the carbon atom coordinates corresponding to the random number as a random site for functionalization.

[0014] S44: Based on the quadrant where the obtained random point is located, calculate the angle of the random point relative to the origin of the coordinate system based on the coordinates of the random point, and calculate the rotation matrix, translation matrix and orientation factor corresponding to the spatial coordinate transformation based on the spatial coordinate transformation parameter equation of S1.

[0015] S45: Based on the topology file of the functional group model, obtain the functional group topology information of the random site through the rotation matrix, translation matrix and orientation factor of coordinate transformation, store it in the functional group matrix, and number the functional group.

[0016] S46: Based on the index of random site coordinates and the index marking rules of carbon atoms in ultrafine diamond nanowires, identify and eliminate adjacent carbon atoms in the same carbon ring and carbon atoms in adjacent carbon rings to avoid the concentration of functional groups.

[0017] S47: Update the functionalizable region carbon atom array, and at the same time remove the hydrogen atoms corresponding to the removed carbon atoms, update the corresponding hydrogen atom array, and return to S43; until all functionalizable random sites are determined;

[0018] S5: Based on the array of all random sites of the functional groups, integrate the carbon atom coordinates and hydrogen atom coordinates of the ultrafine diamond nanowire model to obtain the topological information of the overall functionalized model, including the coordinates, type, number and corresponding molecular number information of the atoms.

[0019] Furthermore, step S2 specifically includes the following sub-steps:

[0020] S21: Generate a periodic unit cell model of ultrafine diamond nanowires, and export the periodic unit cell model as a coordinate file and a crystal information file;

[0021] S22: Based on the coordinate file and crystal information file of the periodic unit cell model, obtain the coordinate information and boundary information of the periodic unit cell model, and number the carbon atoms and hydrogen atoms in the periodic unit cell model clockwise and store them separately in two arrays.

[0022] The beneficial effects of this invention are as follows:

[0023] The modeling method of this invention achieves precise positioning and control of functional groups on the surface of diamond nanowires by standardizing functional groups and their coordinate transformation, molecular modeling and controllable random selection of sites for functionalization, and excluding high-energy sites of concentrated functionalization. This helps to carry out quantitative research on the effect of functional groups on the properties of one-dimensional nanomaterials and the effect of functionalized one-dimensional nanomaterials on the properties of modified materials, and to analyze the intrinsic mechanism at the microscale. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the modeling method for functionalization of ultrafine diamond nanowires according to an embodiment of the present invention.

[0025] Figure 2 This is a schematic diagram of the periodic unit cell model and functional group model of ultrafine diamond nanowires.

[0026] Figure 3 This is a schematic diagram of the region where functional groups are added in an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the functional group addition site exclusion points in an embodiment of the present invention, where green represents the rejection points.

[0028] Figure 5 This is a schematic diagram of the functionalized structure of ultrafine diamond nanowires modeled for an embodiment of the present invention. Detailed Implementation

[0029] The present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments. The purpose and effects of the present invention will become clearer. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0030] like Figure 1 As shown, the modeling method for functionalization of ultrafine diamond nanowires of the present invention includes two steps: functional group creation and coordinate transformation, and functionalization of ultrafine diamond nanowires. In this embodiment, all input files are compiled and run in Matlab.

[0031] Step 1: Functional Group Modeling and Coordinate Transformation

[0032] S11: Establish a functional group molecular model according to requirements and obtain a topological file. In this embodiment, the selected functional group is methyl (-CH3), such as... Figure 2 As shown, the carbon and hydrogen atoms of methyl form a tetrahedron in space.

[0033] S12: Read the methyl topology file and establish the spatial coordinate transformation parametric equations of the rotation matrix, translation matrix, and orientation factor based on the coordinates of the functional group model.

[0034] Step 2: Unit cell modeling and data reading of ultrafine diamond nanowires

[0035] S21: Periodic unit cell models of ultrafine diamond nanowires are generated using molecular modeling tools such as Materials Studio or VESTA. Figure 2 As shown, the unit cell model is exported as a .xyz coordinate file and a .cif crystal information file.

[0036] S22: Based on the two topology files in S21, obtain the coordinate and boundary information of the unit cell model, and number the carbon and hydrogen atoms in the unit cell model clockwise and store them separately in two arrays.

[0037] In this embodiment, S2 can be implemented using Matlab programming, but it can also be implemented using C, Python, or other programming languages.

[0038] Step 3: Modeling of ultrafine diamond nanowires

[0039] Based on the principal coordinate direction of the periodic unit cell model of ultrafine diamond nanowires, the length of the diamond nanowires is pre-set, and an ultrafine diamond nanowire model of the required length is established. The carbon and hydrogen atom coordinates of the ultrafine diamond nanowire model are placed into two separate arrays. Then, the center of the bottom surface of the ultrafine diamond nanowire model is transformed to the origin of the coordinate system, with the length direction along the principal coordinate direction of the coordinate system. The completed ultrafine diamond nanowire model is shown below. Figure 3As shown.

[0040] Step 4: Functional group site selection

[0041] Based on the carbon atom coordinates transformed from the ultrafine diamond nanowire model, the sites and proportions of functional groups to be added are defined, while unreasonable functional group addition sites are eliminated. Finally, all carbon and hydrogen atom coordinates of the ultrafine diamond nanowire model are integrated to obtain the topological information of the overall functionalized model. Step four is implemented through the following sub-steps:

[0042] S41: Select the pseudo-functionalized region according to the simulation requirements; store the carbon and hydrogen atom coordinates of the pseudo-functionalized region into the carbon atom array and the corresponding hydrogen atom array of the functionalized region;

[0043] S42: Calculate the total number of functional groups to be added based on the functionalization ratio and the total number of carbon atoms in the functionalizable region.

[0044] S43: Control the random number seed. Based on the array of carbon atoms in the functionalizable region, obtain a random number and extract the carbon atom coordinates corresponding to the random number as a random site for functionalization.

[0045] S44: Based on the quadrant where the obtained random site is located, calculate the angle of the random site relative to the origin of the coordinate system based on the coordinates of the random site, and calculate the rotation matrix, translation matrix and orientation factor corresponding to the spatial coordinate transformation based on the spatial coordinate transformation parameter equation in step one.

[0046] S45: A topology file based on a functional group model. The topology information of the functional group at the random location is obtained through the rotation matrix, translation matrix and orientation factor of the coordinate transformation, stored in the functional group matrix, and the functional group is numbered.

[0047] S46: Based on the indexing rules of random site coordinates and the carbon atom indexing of ultrafine diamond nanowires, identify and eliminate adjacent carbon atoms in the same carbon ring and carbon atoms in adjacent carbon rings to avoid functional group concentration. For example... Figure 4 As shown, the locations of functional group addition sites and exclusion points are illustrated, with green representing exclusion points.

[0048] S47: Update the functionalizable region carbon atom array, and at the same time remove the hydrogen atoms corresponding to the removed carbon atoms, update the corresponding hydrogen atom array, and return to S43; until all functionalizable random sites are determined.

[0049] Step 5: Based on the array of all random sites of the functional groups, integrate the carbon and hydrogen atom coordinates of the ultrafine diamond nanowire model to obtain the topological information of the overall functionalized model, including the coordinates, type, and index of the atoms, and the corresponding molecular index information. The final functionalized structure of the ultrafine diamond nanowire is as follows: Figure 5 As shown.

[0050] After obtaining the topological information of the overall functionalized model, the data file and coordinate file of the functionalized ultrafine diamond nanowire can be output according to the data format requirements. Then, further display or calculation can be performed using molecular model visualization software and molecular dynamics simulation software, such as Ovito and VMD.

[0051] It will be understood by those skilled in the art that the above descriptions are merely preferred examples of the invention and are not intended to limit the invention. Although the invention has been described in detail with reference to the foregoing examples, those skilled in the art can still modify the technical solutions described in the foregoing examples or make equivalent substitutions for some of the technical features. All modifications and equivalent substitutions made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A modeling method for functionalizing ultrafine diamond nanowires, characterized in that, Includes the following steps: S1: Establish a functional group molecular model, and establish spatial coordinate transformation parameter equations for rotation matrix, translation matrix, and orientation factor based on the coordinates of the functional group model; S2: Establish a periodic unit cell model of ultrafine diamond nanowires, and number the carbon and hydrogen atoms in the unit cell model in a clockwise direction; S3: Based on the principal coordinate direction of the periodic unit cell model of the ultrafine diamond nanowire, the length of the diamond nanowire is preset, an ultrafine diamond nanowire model of the required length is established, and the carbon and hydrogen atom coordinates of the ultrafine diamond nanowire model are placed into two arrays respectively. Then, the center of the bottom surface of the ultrafine diamond nanowire model is transformed to the origin of the coordinate system, with the length direction along the main coordinate direction of the coordinate system; S4: Based on the carbon atom coordinates after the transformation of the ultrafine diamond nanowire model, the site regions and the proportion of functional groups to be added are set, while unreasonable functional group addition sites are eliminated. Finally, all carbon atom coordinates and hydrogen atom coordinates of the ultrafine diamond nanowire model are integrated to obtain the topological information of the overall functionalized model. S4 includes: S41: Select a pseudo-functionalized region according to the simulation requirements; store the carbon and hydrogen atom coordinates of the pseudo-functionalized region into the functionalized region carbon atom array and the corresponding hydrogen atom array; S42: Calculate the total number of functional groups to be added based on the functionalization ratio and the total number of carbon atoms in the functionalizable region. S43: Control the random number seed. Based on the array of carbon atoms in the functionalizable region, obtain a random number and extract the carbon atom coordinates corresponding to the random number as a random site for functionalization. S44: Based on the quadrant where the obtained random point is located, calculate the angle of the random point relative to the origin of the coordinate system based on the coordinates of the random point, and calculate the rotation matrix, translation matrix and orientation factor corresponding to the spatial coordinate transformation based on the spatial coordinate transformation parameter equation of S1. S45: Based on the topology file of the functional group model, obtain the functional group topology information of the random site through the rotation matrix, translation matrix and orientation factor of coordinate transformation, store it in the functional group matrix, and number the functional group. S46: Based on the index of random site coordinates and the index marking rules of carbon atoms in ultrafine diamond nanowires, identify and eliminate adjacent carbon atoms in the same carbon ring and carbon atoms in adjacent carbon rings to avoid the concentration of functional groups. S47: Update the functionalizable region carbon atom array, and at the same time remove the hydrogen atoms corresponding to the removed carbon atoms, update the corresponding hydrogen atom array, and return to S43; until all functionalizable random sites are determined; S5: Based on the array of all random sites of the functional groups, integrate the carbon atom coordinates and hydrogen atom coordinates of the ultrafine diamond nanowire model to obtain the topological information of the overall functionalized model, including the coordinates, type, number and corresponding molecular number information of the atoms.

2. The modeling method for functionalization of ultrafine diamond nanowires according to claim 1, characterized in that, S2 specifically includes the following sub-steps: S21: Generate a periodic unit cell model of ultrafine diamond nanowires, and export the periodic unit cell model as a coordinate file and a crystal information file; S22: Based on the coordinate file and crystal information file of the periodic unit cell model, obtain the coordinate information and boundary information of the periodic unit cell model, and store the carbon atoms and hydrogen atoms in the periodic unit cell model separately in two arrays according to clockwise numbering.

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