Corrected Polarizable Embedding: Improving the Induction Contribution to Perichromism for Linear Response Theory

An extension of the polarizable embedding (PE) approach for the computation of perichromatic shifts within linear response theory, termed corrected PE, is presented. It covers the change in induction effects in addition to contributions from electrostatics and nonresonant excitonic coupling and thereby presents a combination of the corrected linear response and the PE method. Using this method, we analyzed the individual contributions for six different excitations from four molecules in different solvents to clarify the question, which effects should be accounted for by a polarizable solvation model? The (vertical) reference excitation energies are evaluated by the means of full quantum mechanical computations of large solute–solvent clusters. Excellent agreement is achieved when both the shift due to the change in induction and nonresonant excitonic coupling in addition to the shift due to electrostatics are accounted for.