基数组叠加错误是否会显著影响CCSD后的纠正?
Vladimir Fishman1, Emmanouil Semidalas1, Margarita Shepelenko1
1Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel.
Journal of computational chemistry
|December 24, 2024
概括
对于后合的集群单,双,三 (CCSD(T)) 计算,对权衡校正的关键不如CCSD(T) 相互作用能量那么大. 对于原子化能量,这些纠正随着更大的基础集和先进的热化学协议而显著减少.
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:
- 结合集群理论,特别是CCSDT,是电子结构计算的高精度方法.
- 基础集叠加错误 (BSSE) 可以影响计算的相互作用能量和原子化能量的准确性.
- 权衡校正通常用于减轻BSSE.
研究的目的:
- 调查对应校正对CCSD后的贡献的影响 (T) 在原子化能量和非共价相互作用基准中.
- 评估BSSE对不同层次的理论和基础集合的重要性.
主要方法:
- 对后CCSD (T) 能源贡献的对权衡纠正的评估.
- 在W4-11总原子化能基准上对BSSE的分析.
- 在A24x8非对应相互作用基准值上对BSSE的分析.
- 使用各种基础集,包括cc-pVDZ,cc-pVTZ和aug-cc-pVTZ.
主要成果:
- 对后CCSD (T) 贡献的对称校正通常比对CCSD (T) 相互作用能量小两倍.
- 连接的四重置换 (Q) 和更高阶激发的BSSE是可以忽略不计的.
- 对于原子化能量,BSSE可以在小基数组 (例如,cc-pVDZ) 中显著,但在更大的基数组和外推方法 (W4,HEAT) 中变得无关紧要.
- 在非共价二次体中,在CCSD后的差异BSSE相关性是可以忽略不计的,即使是小的基础集.
结论:
- 对于非共价相互作用中CCSD后的相关性贡献,对权衡校正的重要性很小.
- 通过标准的高水平热化学协议,BSSE对原子化能的影响被有效地消除.
- 该研究强调了BSSE在更高层次的理论和更大的基础集中的作用正在减少.
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