在双正规的基础上和一个便宜的三体相关系因子的交叉相关的选定配置相互作用
Abdallah Ammar1, Anthony Scemama1, Emmanuel Giner2
1Laboratoire de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, Toulouse, France.
The Journal of chemical physics
|September 21, 2023
概括
这项研究引入了跨对应 (TC) 计算的双直角基础,提高了电离潜力和原子化能量的精度. 新的BIO-TC-SCI方法为复杂的分子系统提供了一个用户友好的方法.
科学领域:
- 量子化学是一种量子化学.
- 计算化学是一种计算化学.
- 理论化学是一种理论化学.
背景情况:
- 标准选择的配置交互 (SCI) 方法在相关计算中的准确性往往面临挑战.
- 跨相关 (TC) 方法提供了一条将电子相关性纳入的途径,但需要仔细选择基础集.
- 哈特里-福克 (HF) 轨道可以导致TC计算中的重大错误,特别是对于诸如电离潜力和原子化能量等属性.
研究的目的:
- 在TC计算的双直角基础内开发SCI的数学框架.
- 在TC方法中研究双直角基比标准HF轨道的优势.
- 评估拟议的BIO-TC-SCI方法对分子性质计算的准确性和适用性.
主要方法:
- 在TC计算中使用双直角基础的SCI数学框架的开发.
- 用双直角轨道与高频轨道得到的结果进行比较.
- 实现一个简单,用户友好的三体相关系数.
- 对14个分子的原子化能量和键解离过程的方法进行测试.
主要成果:
- 双直角基础使得在TC-SCI中能够正确定义冷核心近似值.
- 与HF轨道相比,双直角轨道显著减少了电离潜力和原子化能量的误差.
- 优化的双直角基础减少了二次能量 (PT2) 的正部分,有助于推断技术.
- 对14个分子获得了精确的原子化能量,并实现了大小一致的双键断裂.
结论:
- BiO-TC-SCI方法为电子结构计算提供了强大而准确的方法.
- 使用双直角基础克服了TC方法中与HF轨道相关的局限性.
- 简化相关系因子使BIO-TC-SCI方法对复杂的分子系统具有实用性.
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