论文标题
振动偏振子诱导的能量转移和化学动力学的QM/mm建模
QM/MM Modeling of Vibrational Polariton Induced Energy Transfer and Chemical Dynamics
论文作者
论文摘要
振动强耦合（VSC）提供了一种新颖的方法来改变化学反应和能量转移途径。为了在集体制度中有效地模拟VSC下的化学动力学，在此开发了杂交量子机械/分子机械（QM/mm）腔分子动力学（CAVMD）方案（CAVMD）方案，并将其应用于实验研究的化学系统。通过假设每个QM溶质分子都被独立的MM溶剂浴所包围，这种方法可以相对于在VSC下稀释溶液的分子数来实现线性缩放。在VSC下，将这种方法应用于n-多德烷的Fe（CO）$ _ 5 $的稀释溶液，证明了对暗模式和偏振剂增强分子非线性吸收的极化。这些模拟预测，强烈兴奋的下极化子可能会提供一种能量转移途径，从而选择性地激发赤道CO振动而不是轴向CO振动。此外，这些模拟还直接探测了Fe（CO）$ _ 5 $浆果伪核反应的腔效应，以与最近的二维红外光谱实验进行比较。这种理论方法适用于广泛的其他极化系统，并提供了一种用于探索VSC选择性红外光化学的工具。
Vibrational strong coupling (VSC) provides a novel means to modify chemical reactions and energy transfer pathways. To efficiently model chemical dynamics under VSC in the collective regime, herein a hybrid quantum mechanical/molecular mechanical (QM/MM) cavity molecular dynamics (CavMD) scheme is developed and applied to an experimentally studied chemical system. This approach can achieve linear scaling with respect to the number of molecules for a dilute solution under VSC by assuming that each QM solute molecule is surrounded by an independent MM solvent bath. Application of this approach to a dilute solution of Fe(CO)$_5$ in n-dodecane under VSC demonstrates polariton dephasing to the dark modes and polariton-enhanced molecular nonlinear absorption. These simulations predict that strongly exciting the lower polariton may provide an energy transfer pathway that selectively excites the equatorial CO vibrations rather than the axial CO vibrations. Moreover, these simulations also directly probe the cavity effect on the dynamics of the Fe(CO)$_5$ Berry pseudorotation reaction for comparison to recent two-dimensional infrared spectroscopy experiments. This theoretical approach is applicable to a wide range of other polaritonic systems and provides a tool for exploring the use of VSC for selective infrared photochemistry.
