Nuclear spatial delocalization silences electron density oscillations in 2-phenyl-ethyl-amine (PEA) and 2-phenylethyl-N,N-dimethylamine (PENNA) cations
Nuclear spatial delocalization silences electron density oscillations in 2-phenyl-ethyl-amine (PEA) and 2-phenylethyl-N,N-dimethylamine (PENNA) cations
复制标题
DOI：
10.1063/1.4943273
复制
发表时间：
2016-03-14
影响因子：
4.4
通讯作者：
Robb, Michael A.
中科院分区：
文献类型：
--
作者：
Jenkins, Andrew J.;Vacher, Morgane;Robb, Michael A.
我们模拟电子动力学电离后，在2-苯基乙基胺和2-苯基乙基-N，N-二甲胺作为系统的例子，其中涉及3耦合阳离子状态。我们研究了两种核效应对电子动力学的影响：（i）电子-核耦合运动和（ii）中性分子中零点能引起的核空间离域。在Escherichfest近似下，我们的计算表明，这些分子中的相干电子动力学并没有失去耦合的电子-核运动的结果。相比之下，作为核空间离域的结果，振荡的失相发生在仅几fs的时间尺度上，远在任何显著的核运动发生之前。结果已合理化使用的半定量模型的基础上的势能面的梯度。(C)2016 AIP Publishing LLC.
We simulate electron dynamics following ionization in 2-phenyl-ethyl-amine and 2-phenylethyl-N,N-dimethylamine as examples of systems where 3 coupled cationic states are involved. We study two nuclear effects on electron dynamics: (i) coupled electron-nuclear motion and (ii) nuclear spatial delocalization as a result of the zero-point energy in the neutral molecule. Within the Ehrenfest approximation, our calculations show that the coherent electron dynamics in these molecules is not lost as a result of coupled electron-nuclear motion. In contrast, as a result of nuclear spatial delocalization, dephasing of the oscillations occurs on a time scale of only a few fs, long before any significant nuclear motion can occur. The results have been rationalized using a semi-quantitative model based upon the gradients of the potential energy surfaces. (C) 2016 AIP Publishing LLC.