在液态水中,电离诱导的质子和能量转移
Ludger Inhester1,2, Arturo Sopena Moros1, Sam Macé1,3
1Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
The Journal of chemical physics
|April 15, 2025
概括
液态水的电离触发了快速的质子转移动态,转移时间因轨道而异. 这一过程影响了分子间库伦比衰变和内部转换途径.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 量子力学就是量子力学.
背景情况:
- 液态水对电离的反应对于理解辐射损伤和化学过程至关重要.
- 价值电离包括从最外围的轨道中去除电子,显著改变分子稳定性.
- 以前的实验研究暗示了水电离后的复杂动态.
研究的目的:
- 以计算方式研究在价值电离后液态水的超快动力学.
- 为了确定不同电离轨道的质子转移和内部转换的时间尺度.
- 为了比较减法和静电嵌入方案对电离化动态的影响.
主要方法:
- 最初进行了分子动力学模拟.
- 模拟涵盖了所有价值轨道 (1b1,3a1,1b2,2a1) 的电离.
- 采用了两个嵌入方案 (减法和静电) 并进行了比较.
主要成果:
- 任何一个价值轨道中的电离会启动快速的质子转移动态.
- 质子转移时间尺度各不相同:2a1的22 fs,1b1的46 fs,3a1的70 fs,1b2的91 fs.
- 电离会导致振动激发,增加局部温度,在数百 femtoseconds 的时间内散热.
- 分子间库伦比衰变与质子转移竞争,以获得2a1电离.
结论:
- 电离价值轨道的类型决定了液态水中质子转移的时间尺度.
- 超快速的质子转移和内部转化是水电离后的关键途径.
- 计算方法,包括不同的嵌入方案,准确地捕捉这些复杂的动态.
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