将核运动纳入激光驱动的ab initio电子动力学的近似方案:应用到高波生成
Paul Anton Albrecht1, Christoph Witzorky1, Peter Saalfrank1,2
1Universität Potsdam, Institut für Chemie, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam-Golm, Germany.
The journal of physical chemistry. A
|July 7, 2023
概括
这项研究引入了一种新方法,可以在attosecond激光相互作用期间准确地模拟复杂分子中的量子核运动. 这种方法可以改进超快电子动态和高波生成 (HHG) 的模拟.
科学领域:
- 量子化学 是一个量子化学.
- 理论上的阿托化学理论上的阿托化学
- 分子动力学分子动力学
背景情况:
- 在短激光脉冲下模拟分子中的多电子动力学对于理论的attochemistry至关重要.
- 包括量子核运动在内是计算密集的,往往导致计算中的固定核近似.
- 之前对H2+的研究表明,核运动显著影响高波生成 (HHG) 频谱.
研究的目的:
- 开发一种计算上可行的方法,在复杂的分子系统中包含量子核运动.
- 扩大对合核电子动态的处理范围,超越像H2+这样的简单系统.
- 为了能够准确地模拟具有多个电子和原子核的分子中的超快电子动态和HHG.
主要方法:
- 使用模型潜能 (和和非对称扩张) 的波恩-奥本海默潜在能量表面的近似值.
- 从一组最小的初始计算中推导模型潜力.
- 在电子结构计算中应用时间依赖的配置交互 (TD-CIS).
主要成果:
- 成功验证了在H2+中使用少数周期激光脉冲检测HHG的方法,并与精确的计算相匹配.
- 适用于具有多个电子的二原子分子,证明了更广泛的适用性.
- 扩展到水分子的二维模型,展示其对更复杂系统的潜力.
结论:
- 拟议的方案有效地将量子核运动纳入复杂分子的 attochemistry 模拟.
- 从ab initio数据中获得的模型潜力提供了一种计算效率高的处理核动力学的方法.
- 这种方法为对光驱动分子过程进行更准确的理论研究铺平了道路.
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