解码化学键:与QTAIM相比,对重叠电子密度描述器和拓性质的基准效应的评估
Carlos V Santos1, Shirlene A Monteiro2, Amanda S C Soares3
1Department of Chemistry, Federal University of Paraiba, Joao Pessoa, Paraiba 58051-970, Brazil.
新的重叠属性 (OPs) 和重叠密度拓 (TOP) 描述符减少了量子化学键分析中的基础集合依赖性. 这些方法提供可靠的化学见解,计算成本较低.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学计算化学
- 化学结合理论 化学结合理论
背景情况:
- 来自电子密度的量子化学键描述器,为化学相互作用提供了洞察力.
- 这些描述符往往对所选择的基础集表现出敏感性,影响其可靠性.
- 减少基数组的依赖性对于开发强大且计算效率高的描述符至关重要.
研究的目的:
- 引入和评估新的重叠属性 (OPs) 和重叠密度 (TOP) 描述符的拓.
- 将OP和TOP描述符的基础集合依赖性与现有的分子中的原子量子理论 (QTAIM) 描述符进行比较.
- 评估这些新描述物的化学意义和可靠性,跨越各种化学键.
主要方法:
- 电子密度的数值处理以获得OP和TOP描述符.
- 使用28个基础集 (Pople,Ahlrichs,Dunning) 在理论的 ωB97X-D 级别对基础集依赖性的分析.
- 将OP/TOP描述符与QTAIM描述符对单 (C-C,C-O,C-F) 和双 (CC,CO) 键,以及二原子分子 (Li-X) 的比较.
主要成果:
- 拓重叠电子密度属性 (TOP) 的依赖性明显低于总电子密度对应的依赖性.
- 与QTAIM描述符相比,数字OP描述符的依赖性较低.
- 特定的基准集 (Def2TZVP, 6-31++G(d,p), 6-311++G(d,p),cc-pVDZ,cc-pVTZ,cc-pVQZ) 显示出变化的减少,其中阿尔里希斯的三次ζ质量特别有效.
结论:
- 叠加性质 (OPs) 和叠加密度拓 (TOP) 是减少基数组依赖的化学键分析的有希望的描述符.
- 这些新型描述符即使在最小化的基础设置影响下也保持了化学意义,提供了更强大的方法.
- 提供了关于合理选择基数组的建议,建议不要使用过度极化功能的基数组.
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