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Vishal Kumar Jaiswal¹, Mario Taddei¹, Daniel R Nascimento²

¹Dipartimento di Chimica Industriale, Università degli Studi di Bologna, Bologna, Italy.

Photochemistry and photobiology

|February 15, 2024

概括

将时间依赖密度函数理论 (TD-DFT) 和DNA光诱导动态的CASPT2方法进行比较,可以发现类似的潜在能量表面拓. 改进的环境建模纠正了TD-DFT.

科学领域:

计算化学是一种计算化学.
摄影化学的使用.
分子动力学分子动力学

背景情况:

时间依赖密度函数理论 (TD-DFT) 和多配置二阶扰动理论 (CASPT2) 是研究DNA光诱导动态的关键方法.
在使用量子力学/分子力学 (QM/MM) 协议时,这些方法在生理环境中可以产生不同的结果.
了解这些差异对于准确的DNA光化学建模至关重要.

研究的目的:

用TD-DFT和CASPT2比较DNA系统中电子状态的潜在能量表面 (PES) 和光诱导动力学.
研究量子力学/分子力学 (QM/MM) 协议和环境建模对这些动态的影响.
确定导致TD-DFT和CASPT2之间的差异的因素,特别是尿素测试案例.

主要方法:

对于水溶尿素,在QM/MM水平上进行了表面跳跃动态模拟.
计算使用了TD-DFT和CASPT2电子结构方法.
分析的重点是潜在能量表面的拓和激发状态寿命.

主要成果:

参与光诱导放松的电子状态潜在能量表面的底层拓在TD-DFT和CASPT2.2之间是相似的.
被限制在S1状态的表面跳动动态显示了两种方法的可比能量波动和放松寿命.
具有标准QM/MM静电嵌入的TD-DFT倾向于低估S2状态的能量,导致错误的状态排序和异常的兴奋状态寿命.
改进的环境描述 (可极化嵌入或扩展的QM层) 恢复了TD-DFT中正确的状态排序.

结论:

TD-DFT和CASPT2为DNA系统中的光诱导动力学提供了类似的PES拓.
通过采用精确的环境建模技术,可以显著提高TD-DFT对DNA光诱导动态建模的准确性.
当与先进的QM/MM协议相结合时,TD-DFT成为研究DNA和RNA系统中光诱导动态的可行和高效方法.

关键词:

这是PCM的PCM.QM/MM QM/MM QM/MM QM/MM QM/MM QM/MM QM/MM QM/MM QM/MM QM/MM QM/MM QM/MM QM/MM 兴奋的状态兴奋的状态在飞行中的动态.可偏振嵌入式嵌入式尿素尿素尿素

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