由外部电磁场引起的内部转换
R R Valiev1, R T Nasibullin2, B S Merzlikin2
1Department of Chemistry, Faculty of Science, P.O. Box 55 (A.I. Virtanens plats 1), FIN-00014 University of Helsinki, Helsinki, Finland. valievrashid@gmail.com.
Physical chemistry chemical physics : PCCP
|January 11, 2024
概括
外部电场显著影响内部转换率常数 (k_IC),与高电场强度的k_IC本身相比. 在典型的实验条件下,磁场对k_IC的影响微不足道.
科学领域:
- 物理化学 物理化学
- 计算化学的计算化学
- 光物理学的光学物理学
背景情况:
- 内部转化 (k_IC) 是一个关键的光物理过程,影响分子激发状态寿命.
- 外部电场和磁场可能会影响分子电子特性和动态.
- 了解场诱导效应对于解释涉及强场的实验至关重要.
研究的目的:
- 开发一种方法来计算电磁场对内部转换率常数 (k_IC) 的贡献.
- 量化这些场对代表分子的k_IC的影响.
- 评估这些效应在各种实验环境中的相关性.
主要方法:
- 开发一种新的理论框架来计算对k_IC的现场诱导贡献.
- 将该方法应用于七个不同的分子系统.
- 在不同场强度下估计k_IC-E和k_IC-M的贡献.
主要成果:
- 外部电场 (k_IC-E) 可以显著增强k_IC,通常与10^11 V m^-1.的无电场速率相匹配.
- 对于特定的分子 (例如,绿色的氨酸),即使在 10^9 V m^-1.0 时,也观察到显著的 k_IC-E 效应.
- 磁场对k_IC的贡献 (k_IC-M) 在陆地条件下可以忽略不计,但在极端天体物理环境中是显著的.
结论:
- 电场对k_IC的影响必须在使用强电场的实验 (例如,等离子体学,激光场研究) 的光物理计算中考虑.
- 磁场对k_IC的影响在地球上通常是可以忽略不计的,但对于中子星和白矮星附近的天体物理现象是很重要的.
- 这项工作为预测和理解场依赖光物理过程提供了一个新的工具.
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