Remarks on the dynamic perturbation effects upon the circular dichroism intensity for chromophore aggregates in the Frenkel exciton model

Abstract

The dynamic perturbation effects of polarizable chromophoric perturbers upon the circular dichroism intensity arising from absorption transitions of an arbitrary chromophore aggregate in the Frenkel exciton model were formulated on the basis of an extended linear response model which is adaptable for treating the dynamic perturbation as an internal electric field perturbation arising from interchromophoric multipolar interactions. The interchromophoric retardation phase factors were eliminated by a first-order Taylor expansion which is compatible with the use of the retarded helix selection rules under the long-wavelength approximation. In the limit of the weak dynamic perturbation a space-averaged closed-form expression of the nonconservative circular dichroism intensity which is perturbed by intensity sharing with the perturber transitions was derived by means of the projection operator method to partition the full resolvent operator.