什么控制了光动力学模拟的质量? 电子结构与非adiabatic算法对比
1Department of Physical Chemistry, University of Chemistry and Technology, Technická 5, 16628 Prague 6, Czech Republic.
Journal of chemical theory and computation
|November 8, 2023
概括
电子结构方法显著影响非相应动力学模拟,即使潜在能量表面看起来相似. 在这项关于环胺动态的研究中,算法性能没有显示出明显的差异.
科学领域:
- 计算化学的计算化学
- 量子动力学 量子动力学是什么?
- 摄影化学的使用
背景情况:
- 非相应动力学模拟对于理解光化学过程至关重要.
- 众所周知,选择电子结构方法会影响模拟结果.
- 在非adiabatic动态中,电子结构方法的灵敏度分析经常被忽视.
研究的目的:
- 调查非adiabatic动态对各种电子结构方法和算法的敏感性.
- 用一套多样化的计算方法来分析环罗巴的非adiabatic动态.
- 评估电子结构选择对模拟准确性的影响.
主要方法:
- 基于波函数 (CASSCF,FOMO-CASCI,MS-CASPT2,XMS-CASPT2) 和密度函数 (REKS) 的方法进行比较.
- 包括半实证 (MRCI-OM3) 电子结构方法.
- 使用兰道-泽纳表面跳跃,最少交换机表面跳跃,以及ab initio多个产卵算法.
主要成果:
- 电子结构方法的选择显著影响了循环罗巴的非adiabatic动态的准确性.
- 潜在能量的表面表现出质量和数量上的相似性并不能保证一致的模拟结果.
- 在测试的非adiabatic动态算法中没有观察到显著的性能差异.
结论:
- 仅仅依靠潜在能量表面映射来选择电子结构可能会产生误导.
- 选择电子结构方法对于可靠的计算光动力学至关重要.
- 该研究强调了在非adiabatic动态中需要严格的电子结构灵敏度分析的需要.
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