"最好的"代配对集群三倍模型? 更多关于3CC的证据
Nakul K Teke1, Ajay Melekamburath1, Bimal Gaudel1
1Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States.
The journal of physical chemistry. A
|October 31, 2024
概括
3CC方法提供比标准CCSDT和CCSDT模型更准确的计算热化学. 这种方法为高精度的电子结构计算提供了具有成本效益的替代方案.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 电子结构理论 电子结构理论
背景情况:
- 合集群 (CC) 模型对于准确的电子结构计算至关重要.
- 大约包括3体集群已经显示出改善CC模型性能的希望.
- 标准的CCSDT模型虽然准确,但在计算上可能很昂贵.
研究的目的:
- 综合评估计算热化学的三体合集群 (3CC) 方法的性能.
- 为了评估3CC的准确性与HEAT框架内的高级参考 (CCSDTQ) 相比.
- 为了研究3CC作为一个潜在的后CCSD (T) 方法.
主要方法:
- 实施了一种新的自旋集成3CC方法,适用于封闭和开放系统.
- 开发了一种自动化工具链,用于导出,优化和评估在多体电子结构中的运算子代数.
- 使用双ζ基数组进行了计算,并推算到完整的基数组极限.
主要成果:
- 在使用双ζ基数组时,3CC方法在电子和原子化能量方面的平均绝对误差明显低于CCSDT和CCSDT.
- 在完整的基础设置极限中,3CC原子化能量与CCSD相比显示出显著的误差减少.
- 3CC方法在CBS极限中对原子化能产生了0.52kJ/mol的平均绝对误差,超过了CCSD (T) (1.07kJ/mol).
结论:
- 3CC方法是CCSD后热化学应用的可行和准确的候选者.
- 3CC为一般电子结构计算提供了比CCSDT更准确和更具成本效益的替代方案.
- 开发的自动化工具链有助于将3CC应用于各种化学系统.
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