在半退化的N电子价值扰乱理论中,对旋转轨道合和动态相关性进行一致的二次处理
Rajat Majumder1, Alexander Yu Sokolov1
1Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States.
Journal of chemical theory and computation
|May 25, 2024
概括
我们开发了二次半退化的N电子价值扰动理论 (QDNEVPT2) 方法,以准确描述电子状态中的自旋轨道合和动态相关性. DKH2-QDNEVPT2的准确性与各种系统的相对论理论相美.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学计算化学
- 理论化学 理论化学
背景情况:
- 精确处理旋转轨道合 (SOC) 和动态相关性对于多配置电子状态至关重要.
- 现有的方法往往难以平衡这些影响,特别是在几乎退化的状态.
研究的目的:
- 制定和实施二阶半退化N电子价值扰动理论 (QDNEVPT2) 方法.
- 为了实现一个平衡和准确的SOC和电子状态的动态相关性描述.
- 为了评估新的QDNEVPT2方法的性能与既有相对论理论相比.
主要方法:
- 开发了第二阶段的QDNEVPT2,将电子排斥和SOC运算符作为扰动.
- 采用布雷特-保利 (BP) 和道格拉斯-克罗尔-赫斯 (DKH) 哈密尔顿因 SOC 效应在旋转轨道平均场近似内.
- 在紧的非相对论基础上诊断出有效的哈密尔顿式来治疗几乎退化的状态.
主要成果:
- 引入了BP2和DKH2-QDNEVPT2方法,实现了准确的SOC和动态相关性描述.
- 对于各种原子和分子,DKH2-QDNEVPT2的准确性与变化的二元相对论理论相竞争.
- BP2-QDNEVPT2对于较轻的元件显示了高精度,但对于较重的系统显示了降低的精度.
结论:
- DKH2-QDNEVPT2是一个有前途的准确和高效的电子结构计算方法,涉及SOC和电子相关性.
- BP1-和DKH1-QDNEVPT2提供可靠但不太准确的替代品.
- 这些QDNEVPT2方法对于需要精确处理电子相关性和SOC的各种应用非常有价值.
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