通过表面跳跃模拟来解决光诱导的Femtosecond三维溶液-溶剂动力学
Severin Polonius1,2, David Lehrner1, Leticia González1,3
1Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria.
Journal of chemical theory and computation
|May 20, 2024
概括
在溶液中模拟光诱导动力学需要先进的方法. 一种新的计算效率高的方法 (LVC/MM) 可实现精确的溶剂动力学模拟,揭示了键如何在激发后断裂和重构.
科学领域:
- 计算化学计算化学
- 物理化学 物理化学
- 频谱学是一种光谱学.
背景情况:
- 溶液-溶剂相互作用控制着光诱导的动力学,导致了诸如溶染色体和电荷转移等现象.
- 精确模拟这些动态需要解决溶液光刺激和同时3D溶剂分布.
- 传统的方法,如轨迹表面跳跃 (TSH) 与QM/MM是计算上昂贵的大规模模拟.
研究的目的:
- 引入和应用具有分子力学 (LVC / MM) 方法的计算效率高的线性振动合模型来模拟光诱导动力学.
- 解开水中的硫基化合物的光诱导动力学,重点关注溶解物-溶剂相互作用和键重组.
- 建立一个方法来估计无噪声溶剂分配函数所需的轨迹数量.
主要方法:
- 使用的轨迹表面跳跃 (TSH) 与一种新的分子力学 (LVC/MM) 方法的线性振动合模型相结合.
- 使用静电嵌入用于嵌入溶剂,非adiabatically合的潜在能量表面.
- 模拟了大约1万个轨迹3皮秒,以分析溶剂分布和电子动态.
主要成果:
- 证明LVC/MM方法的尺度类似于分子力学力场,显著降低计算成本.
- 观察到平面内与基态中的硫原子的键,在激发时与分子平面垂直地断裂和重构.
- 揭示了溶剂放松动力学与电子动力学相结合,包括系统间交叉,具有不同的键改革时间表.
结论:
- LVC/MM方法提供了一个计算上可行的途径,可以准确模拟合溶液-溶剂光诱导动力学.
- 这项研究阐明了电子激发,键动态和硫化合物中的溶剂放松之间的复杂相互作用.
- 这些发现有助于更好地理解溶液中的光激发分子,并对生物相关分子如核基具有重要意义.
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