正交与非正交定域分子轨道的定域性评估  

Assessment of the Localization Quality:Orthogonal Versus Non-Orthogonal Localized Molecular Orbitals

作　　者：顾凤龙[1] 刘巧云 彭亮[1] GU Fenglong;LIU Qiaoyun;PENG Liang(Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education∥School of Chemistry andEnvironment, South China Normal University, Guangzhou 510006,China)

机构地区：[1]教育部环境理论化学重点实验室∥华南师范大学化学与环境学院,广州510006

出　　处：《华南师范大学学报（自然科学版）》2018年第5期30-38,共9页Journal of South China Normal University(Natural Science Edition)

基　　金：国家自然科学基金项目(21673085);广东省珠江学者项目(粤财教[2012]40号)

摘　　要：文中总结了正则分子轨道(CMO)、正交定域分子轨道(OLMO)及非正交定域分子轨道(NOLMO)相应的理论,并引入轨道延展度来衡量每种方法生成的分子轨道的定域性能差异、每种方法相对于传统的正则分子轨道其延展度得到提高的比例.通过计算和分析一些典型分子体系的轨道延展度,结果发现:对于占据轨道而言,NOLMO的定域性要比OLMO(通过Boys、Edmiston-Ruedenberg和Pipek-Mezey方法得到)的定域性更好,这也与之前已经发表的非正交定域分子轨道的定域性比正交定域分子轨道提高10%～28%的理论相符.The formulas of canonical molecular orbitals(CMO),orthogonal localized molecular orbital(OLMO)and non-orthogonal localized molecular orbital(NOLMO)to generate molecular orbitals are given.The orbital spread functions of some testing systems and their reduced percentage compared to the canonical molecular orbitals to assess the localization quality of each method were introduced.It is found that for the occupied orbitals,NOLMO is much more localized than CMOs and OLMOs(generated with Boys,Edmiston-Ruedenberg(ER),and Pipek-Mezey(PM)method)if the same cutoff threshold is applied.This is consistent with the theory in the previously published works that the localization of NLOMO is about 10%-28% better than those of any other OLMO method.

关 键 词：正交定域分子轨道 非正交定域分子轨道 定域性 轨道延展度 

分 类 号：O641.121[理学—物理化学]