在大型系统和周期系统中分散相互作用的聚合在分子中的局部相关性方法
Wei Li1, Yuqi Wang1, Zhigang Ni2
1Key Laboratory of Mesoscopic Chemistry of Ministry of Education, New Cornerstone Science Laboratory, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
Accounts of chemical research
|November 22, 2023
概括
分子中的集群 (CIM) 方法可以为大型系统进行准确的电子相关性计算. 该方法通过使用局部化分子轨道,将后哈特里-福克 (后HF) 方法扩展到复杂的化学系统,包括凝缩相.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 材料科学 材料科学 材料科学
背景情况:
- 非共价相互作用,特别是分散,对于化学系统的结构和稳定性至关重要.
- 密度函数理论 (DFT) 与实证分散校正被广泛使用,但有局限性.
- 传统的后哈特里-福克 (后HF) 方法提供更高的准确性,但对于大型和周期性系统来说,计算成本昂贵.
研究的目的:
- 将精确的哈特里-福克后 (HF后) 方法的适用性扩展到大型分子和冷凝相系统.
- 开发和实施高效的计算方法来计算复杂系统中的电子相关能量.
- 为了能够准确地研究分散相互作用起着重要作用的系统.
主要方法:
- 开发和应用聚类在分子 (CIM) 局部相关性方法.
- 在各种电子相关度水平上实施CIM:MP2,CCSD和CCSD.
- 将CIM方法扩展到使用周期边界条件 (PBC-CIM) 的冷凝相系统,并具有局部的Wannier函数.
主要成果:
- 在非常大的系统中,CIM方法允许高精度的电子相关计算,克服了传统后高频方法的局限性.
- 基于CIM的方法,包括CIM-MP2和CIM-DLPNO-CCSD,已成功应用于几何优化,结合能量的计算和反应屏障研究.
- 这种PBC-CIM变体可以对周期系统进行准确的相关能量计算,包括分子晶体的凝聚能和吸附能.
结论:
- 分子中的集群 (CIM) 方法是一种强大的理论工具,用于在大型和凝聚相系统中准确的能量和结构计算.
- CIM显著扩大了高精度后HF计算的范围,以涉及大量分散相互作用的系统.
- 该方法预计将成为研究由非共价力支配的复杂化学现象的必不可少的方法.
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