使用没有波函数的潜在能量表面信息计算的非adiabatic导数合:ab initio和机器学习实现
Wen-Kai Chen1,2, Sheng-Rui Wang2, Xiang-Yang Liu3
1Hebei Key Laboratory of Inorganic Nano-Materials, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024, China.
Molecules (Basel, Switzerland)
|May 27, 2023
概括
一个近似的算法使用潜在能量表面 (PES) 计算非adiabatic合矩阵元素 (NACMEs). 这种方法与机器学习相结合,为多原子系统提供了准确和高效的NACME计算.
科学领域:
- * 理论化学 理论化学
- * 计算化学 计算机化学
- * * 量子化学 量子化学
背景情况:
- * 非合性合矩阵元素 (NACMEs) 对于理解多原子系统动态至关重要.
- * 准确的NACME计算在计算上很苛刻,通常需要基于波函数的方法.
- *现有的方法在可扩展性和适用于各种电子结构方法方面面临挑战.
研究的目的:
- * 实施和验证用于计算NACME的近似算法.
- * 评估基于 PES 的算法与基于波函数的方法之间的准确性.
- * 评估将算法与机器学习模型相结合的效率和准确性.
主要方法:
- * 开发了一个近似的算法来计算NACME,仅使用潜在能量表面 (PES) 信息 (能量,梯度,Hessians).
- * 将算法应用于CH2NH系统,以与基于波函数的精确计算进行比较.
- * 集成了机器学习 (ML) 模型与基于 PES 的近似算法,以提高效率.
主要成果:
- *基于PES的近似算法产生了高度准确的NACME,与基于波函数的方法相比.
- * 精度保持,除了在能量退化的点 (形交叉点) 之外.
- * ML集成方法提供了同样准确的NACME,显著提高了计算效率.
结论:
- *基于PES的近似算法为NACME计算提供了一个可行的和准确的替代方案.
- * 它与各种电子结构方法和ML模型的兼容性扩大了其适用性.
- * 这项工作有助于在更大,更复杂的系统中研究非adiabatic动态.
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