Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, 82 Wood Lane, W12 0BZ London, United Kingdom.
Department of Physics, Imperial College London, Blackett Lab, Prince Consort Road, SW7 2BW London, United Kingdom.
J Chem Phys. 2022 Jun 28;156(24):244114. doi: 10.1063/5.0093780.
In this work, we have studied the nuclear and electron dynamics in the glycine cation starting from localized hole states using the quantum Ehrenfest method. The nuclear dynamics is controlled both by the initial gradient and by the instantaneous gradient that results from the oscillatory electron dynamics (charge migration). We have used the Fourier transform (FT) of the spin densities to identify the "normal modes" of the electron dynamics. We observe an isomorphic relationship between the electron dynamics normal modes and the nuclear dynamics, seen in the vibrational normal modes. The FT spectra obtained this way show bands that are characteristic of the energy differences between the adiabatic hole states. These bands contain individual peaks that are in one-to-one correspondence with atom pair (+·) ↔ (·+) resonances, which, in turn, stimulate nuclear motion involving the atom pair. With such understanding, we anticipate "designer" coherent superpositions that can drive nuclear motion in a particular direction.
在这项工作中，我们使用量子 Ehrenfest 方法，从局域空穴态出发，研究甘氨酸阳离子中的核和电子动力学。核动力学既受初始梯度控制，也受电子动力学（电荷迁移）产生的瞬时梯度控制。我们使用自旋密度的傅里叶变换（FT）来识别电子动力学的“简正模”。我们观察到电子动力学简正模与核动力学之间存在同构关系，这在振动简正模中可以看到。以这种方式获得的 FT 谱显示出与绝热空穴态之间能量差特征的带。这些带包含与原子对（+·）↔（·+）共振一一对应的单个峰，而共振反过来又刺激了涉及原子对的核运动。有了这样的理解，我们期待“设计”出可以沿特定方向驱动核运动的相干叠加态。
