可扩展的Ab Initio电子结构方法,用于主要组化学的近化学精度
Yujing Wei1, Sibali Debnath1, John L Weber1
1Department of Chemistry, Columbia University, New York, New York 10027, United States.
The journal of physical chemistry. A
|July 6, 2024
概括
准确的热化学对于主要组元素至关重要. 可扩展的量子化学方法,如DLPNO-CCSD(T) 和局部化ph-AFQMC实现化学精度,偏差小于1kcal/mol.
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.
- 热化学 热化学 热化学
背景情况:
- 准确的热化学对于理解化学反应和特性至关重要.
- 有单元和双元和扰动三元的正规合集群 (CCSD(T)) 是一个基准,但在计算上昂贵.
- 对于较大的系统,需要像DLPNO-CCSD(T) 和局部相弦合集群蒙特卡洛 (ph-AFQMC) 这样的可扩展方法.
研究的目的:
- 为了评估DLPNO-CCSD(T) 和局部ph-AFQMC的主要组元素热化学的精度.
- 将这些可扩展的方法与已建立的数据集进行比较.
- 评估它们是否适合达到化学精度.
主要方法:
- 作为参考,使用单元和双元和扰动三元 (CCSD(T)) 的合集群.
- 采用基于域的本地化对自然轨道合集群与单个和双重和扰动三重 (DLPNO-CCSD(T)).
- 应用本地化相弦合集群蒙特卡洛 (ph-AFQMC).
- 来自G2,G3,W4-11和W4-17数据集的分子的形成热和原子化能量计算.
主要成果:
- 无论是DLPNO-CCSD(T) 还是局部ph-AFQMC都实现了根平方平均偏差低于1kcal/mol.
- 这些结果符合化学准确度的门.
- 最大偏差仅限于2kcal/mol,证明了高精度.
结论:
- DLPNO-CCSD(T) 和局部的ph-AFQMC对于主要组元素热化学非常准确.
- 这些可扩展的方法提供了精确的基准化学数据.
- 它们的精度可以在生物学和材料科学等领域得到更广泛的应用.
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