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Updated: Jul 11, 2025

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CCSD的基准集极限 (T) 能量:明确的相关性与基于密度的基准集纠正

Dávid Mester^1,2,3, Mihály Kállay^1,2,3

¹Department of Physical Chemistry and Materials Science, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Műegyetem rkp. 3., H-1111 Budapest, Hungary.

Journal of chemical theory and computation

|November 11, 2023

概括

基于密度和明确相关的方法有效地减少了量子化学计算中的基数不完整性错误. 密度校正的合集群方法提供了精度和计算成本的竞争平衡.

科学领域:

计算化学的计算化学
量子化学是一个量子化学.
理论化学理论化学

背景情况:

基数不完整性错误是波函数方法的一个重大挑战.
显式相关和基于密度的校正方法旨在减轻这种错误.
以前的方法通常涉及高计算成本.

研究的目的:

为了比较明确相关的和基于密度的基数组校正方法.
通过密度合适来呈现基于密度的方案的高效实施.
评估这些方法在MP2,CCSD和CCSD计算中的性能.

主要方法:

详细比较明确相关的和基于密度的基数组校正方法.
基于密度的方案的高效实施与密度合适的近似.
测试MP2,CCSD和CCSD的完整基准参考集合.

主要成果:

使用CABS校正的Hartree-Fock能量进行基于密度的校正是强大的,但不超过明确相关的方法.
密度校正的CCSD和CCSD (T) 方法在计算上比明确相关的变体便宜 (大约一半的成本).
使用CABS校正和明确相关的MP2贡献来进行CCSD和CCSD的增量方法,可以获得优异的结果 (<1kcal/mol) 且计算费用低.

结论:

基于密度的校正提供了一种计算效率高的方法来减少基准集不完整性错误.
密度校正的合集群方法提供了与明确相关的方法相比具有竞争力的替代方案,因为其计算成本降低了.
拟议的增量方法可以实现高准确度的热化学性质与最小的计算开销.

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