量子力学中的Roothaan-Hartree-Fock(R-H-F)近似计算在原子、分子和材料电子结构计算中具有重要的意义,是其他高精度电子结构计算方法的基础.本工作根据开源网站Basis Set Exchange中丰富的基组资源,利用高斯型基组矩阵元具有解析表达...量子力学中的Roothaan-Hartree-Fock(R-H-F)近似计算在原子、分子和材料电子结构计算中具有重要的意义,是其他高精度电子结构计算方法的基础.本工作根据开源网站Basis Set Exchange中丰富的基组资源,利用高斯型基组矩阵元具有解析表达式的特性,自行编写Roothaan-Hartree-Fock计算程序,可以较为方便的达到高精度的计算结果.同时本工作用不同大小的基组计算了多种原子和离子的基态能量,研究了He、Be、C2+等原子和离子在不同基组下的收敛特性.此外,基于自行编写的R-H-F程序计算得到He、Be、Ne的第一电离能,与实验对比最大误差不超过6.84%.展开更多
The accurate radial expectation values are impoftallt for the study of atom and molecular properties. In this paper, a STO set calculated by Roothaan-Hataee-Fork method was used to design systematically the data base ...The accurate radial expectation values are impoftallt for the study of atom and molecular properties. In this paper, a STO set calculated by Roothaan-Hataee-Fork method was used to design systematically the data base of the radial expectation values of the ground neutral atoms and their orbits (Z=2-54). The values are in well agreement with the results calculated with other methods.展开更多
Hartree-Fock-Roothaan (HFR) calculations for ground states of some atoms, i.e. He, Be, Ne, Ar, and Kr have been performed using minimal basis sets of Slater type orbitals (STOs) with integer and noninteger principal q...Hartree-Fock-Roothaan (HFR) calculations for ground states of some atoms, i.e. He, Be, Ne, Ar, and Kr have been performed using minimal basis sets of Slater type orbitals (STOs) with integer and noninteger principal quan-tum numbers (integer n-STOs and noninteger n-STOs). The obtained total energies for these atoms using minimal basis sets of integer n-STOs are in good agreement with those in the previous literature. On the other hand, for the case of minimal basis sets of noninteger n-STOs, although the calculated total energies of these atoms agree well with the results in literature, some striking results have been obtained for atoms Ar and Kr. Our computational re-sults for the energies of atoms Ar and Kr are slightly better than those in literature, by amount of 0.00222 and 0.000054 a.u., respectively. The improvement in the energies of atoms Ar and Kr may result from the efficient cal-culations of one-center two-electron integrals over noninteger n-STOs. For some atomic ions in their ground state, HFR calculations have been carried out using minimal basis sets of noninteger n-STOs. The obtained total energies for these atomic ions are substantially lower than those available in literature.展开更多
Using the unsymmetrical one-range addition theorems introduced by one of the authors with the help of complete orthonormal sets of $／varPsi ^／alpha $-exponential type orbitals （$／alpha = 1,0, - 1, - 2,...）$, this...Using the unsymmetrical one-range addition theorems introduced by one of the authors with the help of complete orthonormal sets of $／varPsi ^／alpha $-exponential type orbitals （$／alpha = 1,0, - 1, - 2,...）$, this paper presents the sets of series expansion relations for multicentre nuclear attraction integrals over Slater-type orbitals arising in Hartree--Fock--Roothaan equations for molecules. The final results are expressed through multicentre charge density expansion coefficients and basic integrals. The convergence of the series is tested by calculating concrete cases for arbitrary values of parameters of orbitals.展开更多
Simpler formulas are derived for one-range addition theorems for the integer and noninteger n generalized ex- ponential type orbitals, momentum space orbitals, and hyperspherical harmonics with hyperbolic cosine （GET...Simpler formulas are derived for one-range addition theorems for the integer and noninteger n generalized ex- ponential type orbitals, momentum space orbitals, and hyperspherical harmonics with hyperbolic cosine （GETO HC, GMSO HC, and GHSH HC） in position, momentum and four-dimensional spaces, respectively. The final results are expressed in terms of one-range addition theorems of complete orthonormal sets of Ca-exponential type orbitals, Ca- momentum space orbitals and za-hyperspherical harmonics. We notice that the one-range addition theorems for integer and noninteger n-Slater type orbitals and Gaussian type orbitals in position, momentum and four dimensional spaces are special cases of GETO HC, GMSO HC, and GHSH HC. The theorems presented can be useful in the accurate study of the electronic structure of atomic and molecular systems.展开更多
文摘量子力学中的Roothaan-Hartree-Fock(R-H-F)近似计算在原子、分子和材料电子结构计算中具有重要的意义,是其他高精度电子结构计算方法的基础.本工作根据开源网站Basis Set Exchange中丰富的基组资源,利用高斯型基组矩阵元具有解析表达式的特性,自行编写Roothaan-Hartree-Fock计算程序,可以较为方便的达到高精度的计算结果.同时本工作用不同大小的基组计算了多种原子和离子的基态能量,研究了He、Be、C2+等原子和离子在不同基组下的收敛特性.此外,基于自行编写的R-H-F程序计算得到He、Be、Ne的第一电离能,与实验对比最大误差不超过6.84%.
文摘The accurate radial expectation values are impoftallt for the study of atom and molecular properties. In this paper, a STO set calculated by Roothaan-Hataee-Fork method was used to design systematically the data base of the radial expectation values of the ground neutral atoms and their orbits (Z=2-54). The values are in well agreement with the results calculated with other methods.
文摘Hartree-Fock-Roothaan (HFR) calculations for ground states of some atoms, i.e. He, Be, Ne, Ar, and Kr have been performed using minimal basis sets of Slater type orbitals (STOs) with integer and noninteger principal quan-tum numbers (integer n-STOs and noninteger n-STOs). The obtained total energies for these atoms using minimal basis sets of integer n-STOs are in good agreement with those in the previous literature. On the other hand, for the case of minimal basis sets of noninteger n-STOs, although the calculated total energies of these atoms agree well with the results in literature, some striking results have been obtained for atoms Ar and Kr. Our computational re-sults for the energies of atoms Ar and Kr are slightly better than those in literature, by amount of 0.00222 and 0.000054 a.u., respectively. The improvement in the energies of atoms Ar and Kr may result from the efficient cal-culations of one-center two-electron integrals over noninteger n-STOs. For some atomic ions in their ground state, HFR calculations have been carried out using minimal basis sets of noninteger n-STOs. The obtained total energies for these atomic ions are substantially lower than those available in literature.
文摘Using the unsymmetrical one-range addition theorems introduced by one of the authors with the help of complete orthonormal sets of $／varPsi ^／alpha $-exponential type orbitals （$／alpha = 1,0, - 1, - 2,...）$, this paper presents the sets of series expansion relations for multicentre nuclear attraction integrals over Slater-type orbitals arising in Hartree--Fock--Roothaan equations for molecules. The final results are expressed through multicentre charge density expansion coefficients and basic integrals. The convergence of the series is tested by calculating concrete cases for arbitrary values of parameters of orbitals.
文摘Simpler formulas are derived for one-range addition theorems for the integer and noninteger n generalized ex- ponential type orbitals, momentum space orbitals, and hyperspherical harmonics with hyperbolic cosine （GETO HC, GMSO HC, and GHSH HC） in position, momentum and four-dimensional spaces, respectively. The final results are expressed in terms of one-range addition theorems of complete orthonormal sets of Ca-exponential type orbitals, Ca- momentum space orbitals and za-hyperspherical harmonics. We notice that the one-range addition theorems for integer and noninteger n-Slater type orbitals and Gaussian type orbitals in position, momentum and four dimensional spaces are special cases of GETO HC, GMSO HC, and GHSH HC. The theorems presented can be useful in the accurate study of the electronic structure of atomic and molecular systems.
