A method for obtaining chemical shift of material electron binding energy based on high-throughput quantum mechanics

Abstract

The present invention relates to the technical field of surface characterization of materials. The invention relates to a method for obtaining the chemical shift of electron binding energy of materials based on quantum mechanics high throughput. Firstly, the crystal structure of the material to be studied is obtained, and the crystal structure is optimized by using density functional theory and VASP program. Two CLS calculation methods, namely ∆SCF and orbital energy approximation, are selected to process the crystal structure and electron density of the material. The total ground state energy of the material orbit, the total excited state energy of the material and the energy of a single orbit obtained by different methods are obtained. Finally, the core level electron binding energy (BE) and the chemical shift (CLS) of the core level electron binding energy of the target element in the material are obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of material surface characterization, and in particular to a method for obtaining chemical shift of material electron binding energy based on quantum mechanics high throughput. Background Art

[0002] X-ray photoelectron spectroscopy (XPS) is currently the most commonly used surface characterization method in the fields of materials science, chemistry, and chemical engineering. Moreover, X-ray photoelectron spectroscopy (XPS) is a surface-sensitive technology that can be used to study surface composition and bonding structure, and has unique advantages in characterizing catalyst surface structure and reaction intermediates. More importantly, the core-level electron binding energy BE in an atom is usually more sensitive to the specific chemical environment of the atom. X-ray photoelectron spectroscopy (XPS) can reflect the changes in the chemical environment and electronic structure of the target element in the material by detecting the chemical shift CLS of the core-level electron binding energy.

[0003] At present, due to the limitations of experimental conditions and methods, there are certain difficulties in the analysis of X-ray photoelectron spectroscopy XPS spectra in experiments. In the process of X-ray photoelectron spectroscopy XPS experimental characterization, strict experimental conditions and vacuum environment are required. If the sample is exposed to air, surface contamination will cause deviations in the electron binding energy during the measurement process. In addition, in the process of X-ray photoelectron spectroscopy XPS spectrum analysis, the measured electron binding energy needs to be compared with the standard reference value to distinguish the type information and charge transfer information of different elements. However, at present, for X-ray photoelectron spectroscopy XPS, some electron binding energy information in the basic database is lacking, the accuracy of the data in the database needs to be improved, and it is difficult to establish spectroscopic analysis standards. These reasons have caused confusion in the standard values ​​of electron binding energy of some systems, which has brought certain difficulties to the analysis of X-ray photoelectron spectroscopy XPS spectra, and even made the data misleading.

[0004] Therefore, with the improvement of computing power and the development of methods, theoretical calculations and simulations of core-level electron binding energy and core-level electron binding energy chemical shifts have attracted more and more attention, especially the combination of density functional theory (DFT) calculations based on first principles and the ∆SCF method. The ∆SCF method accurately approximates the electronic structure and takes into account both the ground state and the excited state in the electronic excitation process, so it has high accuracy. However, this method is only applicable to the study of some simple small molecules or pure metals. For more complex systems, the calculation efficiency is low and requires high computing resources and time costs. Enumeration-based theoretical calculations for a large number of systems waste expensive computing resources and require a lot of time and manpower costs, which limits the systematic study of the surface properties of a large number of complex materials. Therefore, more efficient analysis and theoretical prediction of the core-level electron binding energy and core-level electron binding energy chemical shift of target elements in complex materials is an urgent problem to be solved. Summary of the invention

[0005] The technical problem to be solved by the present invention is: how to provide a method for obtaining the chemical shift of material electron binding energy based on quantum mechanics high throughput, and solve the problem of difficulty in analyzing X-ray photoelectron spectroscopy XPS spectra.

[0006] The technical solution adopted by the present invention is: a method for obtaining the chemical shift of material electron binding energy based on quantum mechanics high-throughput, which is carried out in the following steps:

[0007] Step 1, obtaining the crystal structure and unit cell parameters of the target material, and obtaining the crystal structure and unit cell parameters of the target material in the existing crystal material database (such as The Cambridge structural Database, The Inorganic Crystal Structure Database, Crystallography Open Database and other crystal structure databases);

[0008] Step 2: Use density functional theory and VASP program to optimize the crystal structure and unit cell parameters of the target material to find the crystal structure with the lowest energy. The crystal structure and unit cell parameters corresponding to the crystal structure with the lowest energy are the optimized crystal structure and unit cell parameters. Use the Supercell program to perform supercell operation on the optimized crystal structure and unit cell parameters to generate a supercell; prevent the influence of the nuclear holes generated in the process of exciting electrons on other electrons (when the nuclear holes exist, the system is repeatedly charged and discharged). Generally, after the Supercell program, the supercell parameters of the material obtained are about 15Å; 15Å; 15Å. It is most suitable, which can not only ensure the calculation efficiency, but also reduce the influence of the nuclear holes on other electrons.

[0009] Step 3: When the number of supercell atoms of the target material is less than 200, select the ∆SCF method to calculate the electron binding energy chemical shift to obtain the ground state total energy of the target material and the excited state total energy with one nuclear vacancy. The ground state total energy of the target material and the excited state total energy with one nuclear vacancy are calculated by difference to obtain the electron binding energy BE of the target material. The electron binding energy BE of the target material is calculated by comparing it with the electron binding energy BE of its single substance state. ref The difference is the chemical shift CLS, CLS = BE - BE ref ;

[0010] Step 4: When the number of supercell atoms of the target material is greater than or equal to 200, the orbital energy approximation method is selected to perform the electron binding energy chemical shift calculation to obtain the orbital energy of the ground state of the target material and the orbital energy of the target material in different states. The orbital energy of the ground state of the target material and the orbital energy of the target material in different states are approximate to the electron binding energy of the material. The electron binding energy BE of the target material is equal to the electron binding energy BE of its single substance state. ref The difference is the chemical shift CLS, CLS = BE - BE ref .

[0011] The basic principle of the ∆SCF method is to obtain the difference between the total energy of the excited state of the material and the total energy of the ground state when an electron is excited. This calculation has high accuracy, but is relatively time-consuming. Moreover, for materials with a supercell number of atoms greater than or equal to 200, the load is heavy and the efficiency is low. Therefore, this method is selected for materials with an atomic number less than 200; and for supercells with an atomic number greater than or equal to 200, the orbital energy approximation method is selected. The orbital energy approximation method does not require obtaining the total orbital energy of the material, but approximates the energy of the core energy level orbital to the electron binding energy of the orbit. The principle of obtaining chemical shift CLS by this method is relatively simple and efficient, and is more suitable for materials with an atomic number greater than about 200.

[0012] Step a1, using the Wien2k program to obtain the total ground state energy of the target material, that is, the sum of the total orbital energies of the target material in a state where no electrons are excited, using the total electron density of the supercell as input, using the Wien2k program to calculate the sum of the Coulomb interaction force and the exchange-correlation potential to obtain the total potential, introducing the multipole Fourier expansion to calculate the Coulomb interaction force, and obtaining the total potential by summing the Coulomb force and the exchange-correlation potential, using the quadratic variational process to calculate the orbits and eigenvalues ​​of the hybrid functional, and finally obtaining the total ground state energy of the target material and the corresponding ground state crystal structure;

[0013] Step a2, exciting inner electrons to generate nuclear holes, removing a core electron from the total number of electrons in the structure file of the ground state crystal structure of the target material, creating a nuclear hole, and obtaining a target material crystal structure with a nuclear hole; avoiding hole-electron interaction.

[0014] Step a3, obtain the total energy of the excited state, use density functional theory to calculate the total energy of the material with a core hole using the Wien2k program, that is, use the electron density of the crystal structure of the target material with one electron removed as input, obtain the total potential by adding the Coulomb interaction force and the exchange-correlation potential, and use the quadratic variational process to calculate the orbit and eigenvalue of the hybrid functional to obtain the total energy of the excited state of the target material with one core hole.

[0015] Step a4, obtaining the chemical shift CLS, performing difference calculation on the total energy of the ground state of the target material in step a1 and the total energy of the excited state of the target material with one nuclear hole in step a3, and obtaining the electron binding energy BE of the target material. The difference between the electron binding energy BE of the target material and the electron binding energy BEref of the target material in its single substance state is the chemical shift CLS, CLS=BE-BEref.

[0016] In step 3, the orbital energy approximation method has five different orbital energy approximation calculation methods to simultaneously obtain the chemical shift CLS of the electron binding energy of the material. The five different orbital energy approximation calculation methods are initial state orbital energy approximation, transition state orbital energy approximation, final state orbital energy approximation, JS n and FS n ; Initial state orbital energy approximation (initial states, IS), that is, the orbital energy difference in the initial state when no electrons are excited in the material is approximately equal to the electron binding energy of the orbital; transition state orbital energy approximation (Janak-Slater, JS), that is, the orbital energy difference after half of the electrons are excited in the material is approximately equal to the electron binding energy of the orbital, JS n That is, after half an electron is excited, an extra half electron is added to the total number of electrons in the material to keep the total number of electrons unchanged. n That is, after an electron is excited, an extra electron is added to the total number of electrons in the material to keep the total number of electrons unchanged. Selecting the orbital energy approximation method to calculate the electron binding energy chemical shift includes the following steps:

[0017] Step b1, using the VSAP program to calculate the orbital ground state energy of the optimized target crystal structure, input the charge density of the target material crystal structure, calculate the KS eigenvalue of the core energy level orbital, and obtain the ground state orbital energy of the target material;

[0018] Step b2, excite inner electrons to generate nuclear holes, simulate four different photoelectron excitation processes, electrons are removed from the crystal structure of the target material, the number of electrons removed indicates how many electrons are excited from the core energy level orbit of the target material, change the POSCAR and POTCAR files under the VSAP program, the selected atoms correspond to the POTCAR files, the CLNT parameter is the number of excited electrons, to excite one electron of an atom, set CLZ=1, that is, the input setting of the FS method; to excite half an electron of an atom, set CLZ=0.5, that is, the input setting of the JS method; to excite one electron of an atom and keep the overall electrical neutrality of the material, set CLZ=1, add 1 to the total number of electrons, that is, set NELECT=total number of electrons in the initial state, that is, FS n Input settings of the method; to excite half of the electrons of an atom, set CLZ=0.5, add 0.5 to the total number of electrons, that is, set NELECT=total number of electrons in the initial state, that is, JS n Input settings for the method.

[0019] Step b3, high-throughput batch input of the structures of all calculation methods, input of the charge density of the crystal structure of the target material, calculation of the KS eigenvalue of the core energy level orbital, and acquisition of the orbital energy of different states of the target material;

[0020] Step b4, obtain chemical shift CLS, obtain the orbital energy of the ground state of the target material and the orbital energy of the target material in different states, the orbital energy of the ground state of the target material and the orbital energy of the target material in different states are similar to the electron binding energy of the material, the electron binding energy BE of the target material and the electron binding energy BE of its single substance state ref The difference is the chemical shift CLS, CLS = BE - BE ref .

[0021] The simplest relationship for calculating electron binding energy is established by the photoelectric effect, namely:

[0022] BE=hv-E KIN -Ф

[0023] Where hν is the energy of the incident photon, E KINis the kinetic energy of the emitted photoelectron, Ф is the work function of the material, and BE (Binding energy) is the binding energy of the excited photoelectron. The method is selected according to the complexity of the optimized structure and electronic structure. For materials with small electronic structure and unit cell parameters, and for materials with a number of atoms not exceeding 200, the ∆SCF method is generally used. For materials with a large number of electronic structures and atoms (the number of atoms is greater than or equal to 200), in order to reduce manpower and time costs, the orbital energy approximation method is used. After the photoelectrons of the system are excited, the originally stable electronic structure is destroyed, and it is very difficult to solve the state wave function and eigenvalue. The orbital energy approximation adopts Koopman's theorem, that is, the process of photoelectron emission is described as occurring so quickly that other electrons have no time to readjust. That is, compared with the system before ionization, except for one electron being excited in a certain orbit, the motion state of the electrons in the remaining orbits does not change, but is in a "frozen state". Ignore the relaxation effect in the photoemission process, approximate the electron binding to the energy of the orbit, and approximate the orbital energy difference of a specific inner orbit to the electron binding energy of the orbit: BE = the energy of the specified orbit.

[0024] The beneficial effects of the present invention are as follows: the present invention takes the material surface characterization technology as the research object, adopts density functional theory to obtain the core level electron binding energy and the chemical shift of the core level electron binding energy of the target metadata of the material, and obtains the BE and CLS of different materials with very low manpower and time costs based on high-throughput calculation and analysis process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the flow chart of the present invention. DETAILED DESCRIPTION Example

[0026] Step 1. Obtain the crystal structure and unit cell parameters of Fe2C from the CrystallographyOpen Databasebas database. The number of atoms in the unit cell is 6. The unit cell parameters of Fe2C are: 2.82 Å, 4.28 Å, 4.71 Å; 90°, 90°, 90°, and the volume is: 56.98 Å^3.

[0027] Step 2: Use density functional theory Perdew-Burke-Emzerhof and VASP programs to optimize the crystal structure and unit cell parameters of the material. Enter the Fe2C unit cell structure in the program to set the spin and ferromagnetic magnetism. The optimization is completed when the structure with the lowest energy is obtained. The optimized magnetic moment is finally: 2, and the unit cell parameters are: 2.83 Å, 4.28 Å, 4.72 Å; 90°, 90°, 90°. The existing program Supercell is used to set the super cell of the optimized structure of Fe2C to generate a 3×3×3 super cell to avoid the influence of the nuclear hole on other electrons when the nuclear hole exists. The number of atoms in the 3×3×3 super cell is 162, and the unit cell parameters are: 8.49 Å, 12.84 Å, and 14.16 Å.

[0028] Step 3, the number of atoms in the supercell of Fe2C is less than 200. The ∆SCF method is selected to calculate the electron binding energy chemical shift to obtain the ground state total energy of the target material and the excited state total energy with one nuclear vacancy. The ground state total energy of the target material and the excited state total energy with one nuclear vacancy are calculated by difference to obtain the electron binding energy BE of the target material. The difference between the electron binding energy BE of the target material and the electron binding energy BEref of its single substance state is the chemical shift CLS, CLS = BE - BEref;

[0029] Step a1, use the Wien2k program to obtain the total ground state energy of the target material, that is, the sum of the total orbital energy of the target material when no electrons are excited. Use the total electron density of the supercell as input, that is, input the 3×3×3 supercell structure file (cif) format, and perform structure conversion. cif2struct converts the "cif" file into the corresponding format Wien2K case.struct file calculated by Wien2K. After inputting the structure file, use the total electron density of the supercell as input, and obtain the total potential by adding the Coulomb interaction force and the exchange-correlation potential. The orbital and eigenvalues ​​of the hybrid functional are calculated using the quadratic variation process, and finally the crystal structure of Fe2C and the total orbital ground state energy of Fe2C are obtained as: -10334.8039eV.

[0030] Step a2, exciting the inner electrons to generate nuclear holes, removing one core electron from the total number of electrons in the structure file of the ground state crystal structure of the target material, creating a nuclear hole, and obtaining a target material crystal structure with a nuclear hole; avoiding hole-electron interaction.

[0031] Analyze the electronic structure of the target element, excite the electrons in the inner specified orbital, modify the parameters in the Fe2C.inc file, remove the parameter setting of one electron, modify the N, KAPPA, OCCUP parameters to: 2, -2, 3, and set the BG charge to: -1 in the Fe2C.inm file. Remove the electrons in the 2p orbital of the first Fe atom, resulting in an electron core hole, which is completely removed from the system, and obtain the crystal structure of the target material with a core hole.

[0032] Step a3, obtain the total energy of the excited state, use density functional theory to calculate the total energy of the material with a core hole using the Wien2k program, that is, use the electron density after removing one electron as input, obtain the total potential by adding the Coulomb interaction force and the exchange-correlation potential, and use the quadratic variational process to calculate the orbital and eigenvalue of the hybrid functional, and obtain the total energy of the orbital excited state of the material with a core hole: -10283.6454 eV.

[0033] Step a4, obtain chemical shift CLS, calculate the difference between the total energy of the ground state of the target material in step a1 and the total energy of the excited state of the target material with one core hole in step a3, and obtain the difference between the total energy of the excited state and the total energy of the ground state of Fe2C, which is the electron binding energy (BE): BE = -10334.8039 – (-10283.6454) = -51.1585eV. The difference between the electron binding energy BE of the target material and the electron binding energy BEref in its single substance state (the difference between the total energy of the ground state and the total energy of the excited state in the single substance state) is the chemical shift CLS, CLS = BE - BEref. The total energy of the ground state and the total energy of the excited state of 2p of Fe single substance are: -2545.5945eV and -2494.1784eV respectively. That is, the electron binding energy BE value of the 2p orbital of Fe element is: BE(Fe2p) = -2545.5945–(-2494.1784) = -51.4161eV. The difference calculation with the orbital energy of Fe2p in Fe2C is: CLS = -51.1585–(-51.4161 )= 0.2576eV.

[0034] Table 1

[0035] Example

[0036] Step 1. Obtain the crystal structure and unit cell parameters of Fe3C in the CrystallographyOpen Databasebas database. The number of atoms in the unit cell is 16. The unit cell parameters of Fe3C are: 4.49 Å, 5.03 Å, 6.74 Å; 90°, 90°, 90°, and the volume is: 152.24 Å ^3 .

[0037] Step 2: Use the VASP program and the Perdew-Burke-Emzerhof functional to optimize the crystal structure of the material. In step 2, enter the Fe3C unit cell structure in the program and set the spin and ferromagnetic properties. The optimization ends when the lowest energy structure is obtained. The optimized magnetic moment is finally: 3, and the unit cell parameters are: 4.49 Å, 5.03 Å, 6.74 Å; 90°, 90°, 90°. The existing program Supercell is used to set the supercell for the optimized structure of Fe3C, generating a 3×3×3 supercell to avoid the influence of the core hole on other electrons when the core hole exists. The number of atoms in the 3×3×3 supercell is 432, and the unit cell parameters are: 13.47 Å, 15.09 Å, 20.22 Å.

[0038] Step 3, the number of atoms in the supercell of Fe3C is greater than 200, and the orbital energy approximation method is selected to calculate the electron binding energy chemical shift, and the ground state orbital energy of the target material and the orbital energy of the excited state with a nuclear hole are obtained. The difference between the ground state orbital energy of the target material and the orbital energy of the excited state with a nuclear hole is approximately equal to the electron binding energy BE of the material. The difference between the electron binding energy BE of the target material and the electron binding energy BEref of its single substance state is the chemical shift CLS, CLS = BE - BEref;

[0039] Step b1, use the VSAP program to calculate the orbital ground state energy of the optimized target crystal structure (super cell), input the charge density of the super cell structure, calculate the KS eigenvalue of the core energy level orbital, and obtain the ground state orbital energy of the target material; the ground state orbital energy of Fe3C is 682.3128 eV.

[0040] Step b2, excite inner electrons to generate nuclear holes, simulate four different photoelectron excitation processes, electrons are removed from the crystal structure of the target material, the number of electrons removed indicates how many electrons are excited from the core energy level orbit of the target material, change the POSCAR and POTCAR files under the VSAP program, the selected atoms correspond to the POTCAR files, the CLNT parameter is the number of excited electrons, to excite one electron of an atom, set CLZ=1, that is, the input setting of the FS method; to excite half an electron of an atom, set CLZ=0.5, that is, the input setting of the JS method; to excite one electron of an atom and keep the overall electrical neutrality of the material, set CLZ=1, add 1 to the total number of electrons, that is, set NELECT=total number of electrons in the initial state, that is, FS n Input settings of the method; to excite half of the electrons of an atom, set CLZ=0.5, add 0.5 to the total number of electrons, that is, set NELECT=total number of electrons in the initial state, that is, JS n Input settings for the method.

[0041] For the JS and FS methods, it is necessary to remove 0.5 and 1 electrons from the inner orbit of the target element, respectively, to obtain the crystal structure of the material with a core hole. Change the POSCAR and POTCAR files, and select the first Fe atom corresponding to a species in the POTCAR file. The parameter settings of the four methods are:

[0042] Transition state approximation (JS): ICORELEVEL=2 (calculate excited states of core level orbitals), CLNT= 1 (species type), CLN=2 (principal quantum number of excited core level electrons), CLL=1 (angular quantum number of excited core level electrons), CLZ=0.5 (number of excited electrons);

[0043] Final state approximation (FS):ICORELEVEL=2,CLNT= 1,CLN=2,CLL=1,CLZ=1;

[0044] JS n , FS n The method requires not only to remove 0.5 and 1 electrons from the inner orbit of the target element, but also to add 0.5 and 1 electrons to the total electrons to maintain the electrical neutrality of the system. The parameter selections are:

[0045] JS n :ICORELEVEL=2,CLNT=1,CLN=2,CLL=1,CLZ=0.5;NELECT=4968;

[0046] FS n:ICORELEVEL=2,CLNT=1,CLN=2,CLL=1,CLZ=1,NELECT=4968.

[0047] Step b3, high-throughput batch input of the structures of all calculation methods, input of the charge density of the crystal structure of the target material, calculation of the KS eigenvalue of the core energy level orbital, and acquisition of the orbital energy of different states of the target material;

[0048] The VASP program is used to calculate the orbital energy of the material structure with different electrons removed, and the charge density of the different state structures is input to calculate the KS eigenvalue of the core layer state. After the calculation is completed, the 2p energy level orbital energy of the Fe atom is extracted to obtain JS, FS, and JS n , FS n The orbital energies of Fe3C obtained by four different methods are: 707.3336eV; 732.2403eV; 707.9479eV; 732.294eV.

[0049] Step b4, obtain chemical shift CLS, obtain the orbital energy of the ground state of the target material and the orbital energy of the target material in different states, the orbital energy of the ground state of the target material and the orbital energy of the target material in different states are similar to the electron binding energy of the material, the electron binding energy BE of the target material and the electron binding energy BE of its single substance state ref The difference is the chemical shift CLS, CLS = BE - BE ref .

[0050] The 2p orbital energy (BE) of Fe in different states ref ) are, IS: 682.2885eV; JS:707.1448eV; FS:731.7584eV; JS n :707.1559eV; FS n :731.7675eV. The difference between the orbital energy of Fe2p in Fe3C is: CLS(IS)= 682.3128–682.2885 = 0.0243eV;

[0051] CLS(JS)= 707.3336–707.1448 = 0.1888eV;

[0052] CLS(FS)= 732.2403–731.7584 = 0.4819eV;

[0053] CLS(JS n )= 707.9479–707.1559 = 0.792eV;

[0054] CLS(FSn )= 732.294–731.7675 = 0.5265eV.

[0055] The Fe2p chemical shift in Fe3C was obtained by different methods and the results are summarized in Table 1.

Claims

1. A method for obtaining chemical shift of material electron binding energy based on quantum mechanics high throughput, characterized in that: Follow the steps below Step 1: Obtain the crystal structure and unit cell parameters of the target material from an existing crystal material database; Step 2: Use density functional theory and VASP program to optimize the crystal structure and unit cell parameters of the target material to find the crystal structure with the lowest energy. The crystal structure and unit cell parameters corresponding to the crystal structure with the lowest energy are the optimized crystal structure and unit cell parameters. Use Supercell program to perform supercell operation on the optimized crystal structure and unit cell parameters to generate a super unit cell. Step 3: When the number of supercell atoms of the target material is less than 200, select the ∆SCF method to calculate the electron binding energy chemical shift to obtain the ground state total energy of the target material and the excited state total energy with one nuclear vacancy. The ground state total energy of the target material and the excited state total energy with one nuclear vacancy are calculated by difference to obtain the electron binding energy BE of the target material. The electron binding energy BE of the target material is calculated by comparing it with the electron binding energy BE of its single substance state. ref The difference is the chemical shift CLS, CLS = BE - BE ref ; Step 4: When the number of supercell atoms of the target material is greater than or equal to 200, the orbital energy approximation method is selected to perform the electron binding energy chemical shift calculation to obtain the orbital energy of the ground state of the target material and the orbital energy of the target material in different states. The orbital energy of the ground state of the target material and the orbital energy of the target material in different states are approximate to the electron binding energy of the material. The electron binding energy BE of the target material is equal to the electron binding energy BE of its single substance state. ref The difference is the chemical shift CLS, CLS = BE - BE ref .

2. The method for obtaining the chemical shift of electron binding energy of a material based on quantum mechanics high throughput according to claim 1, characterized in that: In step 3, the ∆SCF method is selected to calculate the electron binding energy chemical shift, which includes the following steps: Step a1, using the Wien2k program to obtain the total ground state energy of the target material, that is, the sum of the total orbital energies of the target material in a state where no electrons are excited, using the total electron density of the supercell as input, using the Wien2k program to calculate the sum of the Coulomb interaction force and the exchange-correlation potential to obtain the total potential, introducing the multipole Fourier expansion to calculate the Coulomb potential, and obtaining the total potential by the sum of the Coulomb force and the exchange-correlation potential, using the quadratic variational process to calculate the orbits and eigenvalues ​​of the hybrid functional, and finally obtaining the total ground state energy of the target material and the corresponding ground state crystal structure; Step a2, exciting inner electrons to generate nuclear holes, removing one core electron from the total number of electrons in the structure file of the ground state crystal structure of the target material, resulting in a nuclear hole, and obtaining a target material crystal structure with one nuclear hole; Step a3, obtaining the total energy of the excited state, using density functional theory to calculate the total energy of the material with a core hole using the wien2k program, that is, using the electron density of the crystal structure of the target material with one electron removed as input, obtaining the total potential by adding the Coulomb interaction force and the exchange-correlation potential, and using the quadratic variational process to calculate the orbit and eigenvalue of the hybrid functional to obtain the total energy of the excited state of the target material with one core hole; Step a4, obtain the chemical shift CLS, calculate the difference between the total energy of the ground state of the target material in step a1 and the total energy of the excited state of the target material with a nuclear hole in step a3, and obtain the electron binding energy BE of the target material, the electron binding energy BE of the target material and the electron binding energy BE of the target material in its single substance state ref The difference is the chemical shift CLS, CLS = BE-BE ref .

3. The method for obtaining the chemical shift of material electron binding energy based on quantum mechanics high throughput according to claim 1, characterized in that: In step 4, the orbital energy approximation method has five different orbital energy approximation calculation methods to simultaneously obtain the chemical shift CLS of the electron binding energy of the material. The five different orbital energy approximation calculation methods are initial state orbital energy approximation IS, transition state orbital energy approximation JS, final state orbital energy approximation FS, JS n and FS n The initial state orbital energy is approximately IS, that is, the orbital energy difference in the initial state when no electrons are excited in the material is approximately equal to the electron binding energy of the orbit. The transition state orbital energy is approximately JS, that is, the orbital energy difference after half an electron is excited in the material is approximately equal to the electron binding energy of the orbit. The final state orbital energy is approximately FS, that is, the orbital energy difference after one electron is excited in the material is approximately equal to the electron binding energy of the orbit. JS n That is, after half an electron is excited, an extra half electron is added to the total number of electrons in the material to keep the total number of electrons unchanged. n That is, after exciting an electron, an extra electron is added to the total number of electrons in the material to keep the total number of electrons unchanged.

4. The method for obtaining chemical shift of material electron binding energy based on quantum mechanics high throughput according to claim 3, characterized in that: Selecting the orbital energy approximation method to calculate the electron binding energy chemical shift includes the following steps Step b1, using the VSAP program to calculate the orbital ground state energy of the optimized target crystal structure, input the charge density of the target material crystal structure, calculate the KS eigenvalue of the core energy level orbital, and obtain the ground state orbital energy of the target material; Step b2, excite inner electrons to generate nuclear holes, simulate four different photoelectron excitation processes, electrons are removed from the crystal structure of the target material, the number of electrons removed indicates how many electrons are excited from the core energy level orbit of the target material, change the POSCAR and POTCAR files under the VSAP program, the selected atoms correspond to the POTCAR files, the CLZ parameter is the number of excited electrons, to excite one electron of an atom, set CLZ=1, that is, the input setting of the FS method; to excite half an electron of an atom, set CLZ=0.5, that is, the input setting of the JS method; to excite one electron of an atom and keep the overall electrical neutrality of the material, set CLZ=1, add 1 to the total number of electrons, that is, set NELECT=total number of electrons in the initial state, that is, FS n Input settings of the method; to excite half of the electrons of an atom, set CLZ=0.5, add 0.5 to the total number of electrons, that is, set NELECT=total number of electrons in the initial state, that is, JS n Input settings for the method; Step b3, high-throughput batch input of the structures of all calculation methods, input of the charge density of the crystal structure of the target material, calculation of the KS eigenvalue of the core energy level orbital, and acquisition of the orbital energy of different states of the target material; Step b4, obtaining chemical shift CLS, the difference between the ground state orbital energy of the target material in step b1 and the orbital energy of the target material in different states in step b3 is approximately equal to the electron binding energy BE of the target material, and the electron binding energy BE of the target material is equal to the electron binding energy BE of the target material in its single substance state. ref The difference is the chemical shift CLS, CLS = BE - BE ref .

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