Change transfer mechanism molecular calculations

We solve the Ehrenfest equation for each order of the perturbation and we collect for each order the necessary terms for calculating response functions at the given order. The only part within the Ehrenfest equation that is not covered by the ordinary response theory of quantum mechanical systems in vacuum is represented by the last term on the right hand side of Eq. (66) [80-83]. The contributions to the response functions arising from the last term are related to the presence of the structured environment coupled to the quantum mechanical subsystem, ft is the main contributor to changes in molecular properties when transferring fhe quantum subsystem from vacuum to the structured environment. 

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