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Updated: Jun 28, 2025

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分析梯度使用分子中的集群RI-MP2方法,用于大系统的几何优化

Yang Zheng¹, Zhigang Ni², Yuqi Wang¹

¹Key Laboratory of Mesoscopic Chemistry of Ministry of Education, New Cornerstone Science Laboratory, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China.

Journal of chemical theory and computation

|April 16, 2024

概括

我们开发了一种高效的算法,用于计算分子中的集群识别身份的第二阶Møller-Plesset扰动 (CIM-RI-MP2) 方法中的能量梯度. 这种方法显著降低了大型分子系统的计算成本.

科学领域:

计算化学计算化学
量子化学是一个量子化学.
理论化学理论化学

背景情况:

精确计算分子性质在化学中至关重要.
第二阶梅勒-普莱塞特扰动 (MP2) 理论提供了准确性和成本的良好平衡.
当地MP2方法旨在减少大型系统MP2计算的计算扩展.

研究的目的:

为了呈现一个高效的分析能量梯度算法集群-在-分子辨别-的身份第二阶Møller-Plesset扰动 (CIM-RI-MP2) 方法.
为了证明CIM-RI-MP2梯度算法对大分子的计算效率和适用性.

主要方法:

基于拉格朗日乘法分析能量梯度算法的开发.
在身份解决 (RI) 方程中实施分子中的集群 (CIM) 方法.
避免解决整个系统的合扰乱哈特里-福克 (CPHF) 方程.

主要成果:

与其他本地MP2方法相比,CIM-RI-MP2梯度算法实现了显著较低的计算成本.
对最多312个原子的分子进行的基准计算证实了算法的一般适用性.
一个244原子分子的优化结构与实验晶体结构有很好的一致性.
在48小时内,在25个节点 (600个CPU核心) 上完成了972个原子系统和9612个基本函数的大规模计算.

结论:

开发的CIM-RI-MP2梯度算法对大型分子系统具有计算效率.
该方法适用于获得数百个原子的系统的优化几何形状.
该方法为复杂分子的高精度电子结构计算提供了一个实用的工具.

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