混合量子-经典方法计算电荷转移速率及其在实际体系中的应用(英文)

混合量子-经典方法在复杂分子体系动力学过程的模拟方面有重要应用.我们采用Ehrenfest方法、surfacehopping方法和混合量子经典Liouville方程计算了在非绝热极限下的电荷转移速率.然后将这三种方法应用于有机半导体材料电荷转移速率的计算.研究结果发现,Ehrenfest方法和surface hopping方法可能严重偏离正确的结果.偏离的原因是这两种方法没有正确处理相干项的运动,而且这种偏离在涉及到高频模式时显得更加严重.

Mixed Quantum-Classical Approaches to Calculating Charge Transfer Rate Constants: Applications to Realistic Systems

Mixed quantum-classical methods are of great interest in simulating dynamic processes of complex molecular systems. We investigated the application of the Ehrenfest method, the surface hopping method, and the mixed quantum classical Liouville equation method to calculate charge transfer rates in the nonadiabatic limit. The three methods were applied to realistic problems of charge transfer in organic semiconductor materials. We found that both the Ehrenfest and surface hopping methods may deviate significantly from the correct result. This deviation is due to an incorrect treatment of the coherence term, and is more severe when high frequency modes are involved.