当前位置: X-MOL 学术J. Chem. Theory Comput. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Half-Projection of the Strongly Orthogonal Unrestricted Geminals' Product Wave Function.
Journal of Chemical Theory and Computation ( IF 5.5 ) Pub Date : 2019-12-20 , DOI: 10.1021/acs.jctc.9b00858
Zs É Mihálka 1, 2 , P R Surján 1 , Á Szabados 1
Affiliation  

Half-projection of a wave function built as a product of singlet-triplet mixed two-electron fragments (geminals) is explored. The condition of strong orthogonality is imposed between geminals, the initial Ansatz accommodating the unrestricted Hartree-Fock (UHF) wave function as a special case. The here explored geminal product is more general than UHF, it allowing for single covalent bond breaking in a spin pure manner. The strong correlation present in two geminals simultaneously is accompanied by spin contamination at the geminal product level. Variation after half-projection leads to an eigenvalue problem of an effective two-electron Hamiltonian, conserving the computational economy of the initial model. While the resulting expressions are shown to violate size consistency, quantification reveals a suppressed error with half-projection as compared to the full spin projected then varied scheme. Spin contamination is also found to be diminished compared to the initial, unprojected wave function.

中文翻译:

强正交无限制双子产物波函数的半投影。

探索了由单重态-三重态混合的两个电子碎片(双子星)的乘积建立的波动函数的半投影。双子座之间强正交性的条件是特例,最初的Ansatz容纳了不受限制的Hartree-Fock(UHF)波函数。在这里探索的宝石产品比UHF更通用,它允许以自旋纯净的方式破坏单个共价键。同时存在于两个宝石中的强相关性伴随着宝石产品级别的自旋污染。半投影后的变化导致有效的两电子哈密顿量的特征值问题,从而节省了初始模型的计算经济性。虽然显示结果表达式违反了大小一致性,定量显示与全自旋投影然后变化的方案相比,半投影的误差得到抑制。与初始的非投影波函数相比,还发现自旋污染得以减少。
更新日期:2020-01-09
down
wechat
bug