Exciting molecules with a short strong few cycle IR pulse triggers coherent electronic–nuclear dynamics on multiple electronic states. This creates a new type of initial state where non-adiabatic transfer takes place between already populated electronic states. We explore this new feature using accurate quantal simulations of the ultrafast laser-induced dissociative dynamics in LiH-LiD-LiT series of isotopomers. In this novel type of initial state the non-adiabatic amplitude exchange between the coupled electronic states strongly depends on isotopic composition. The effective non-adiabatic coupling strength is modulated by two counteracting factors. On one hand, the 1/mass factor makes the non-Born–Oppenheimer coupling weaker for the heavier masses. On the other hand, the transfer is modulated by the momentum coupling of the two non-stationary nuclear wave packets on the two electronic states. The magnitude of this coupling tends to be larger for the heavier isotopes and varies ...

中文翻译：

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LiH及其同位素异构体非绝热转变过程中的相关电子核运动

具有短的强几个周期IR脉冲的激发分子会触发多个电子状态的相干电子核动力学。这创建了一种新型的初始状态，在该初始状态中，已经填充的电子状态之间发生了非绝热转移。我们使用LiH-LiD-LiT系列同位素异构体中超快激光诱导的解离动力学的精确定量模拟来探索这一新功能。在这种新颖的初始状态中，耦合电子状态之间的非绝热振幅交换很大程度上取决于同位素组成。有效的非绝热耦合强度由两个抵消因素调节。一方面，1 /质量因数使较重的质量的非伯恩-奥本海默耦合变弱。另一方面，传递是通过两个电子态上两个非平稳核波包的动量耦合来调制的。对于较重的同位素，这种耦合的幅度往往更大，并且变化...