On the magneto-optical properties of polymers in the Frenkel exciton model

Abstract

Fully retarded ellipticity expressions, which are valid for magnetic as well as natural circular dichroism of a polymeric system, are derived via a canonical transformation of the hamiltonian in the Frenkel exciton approximation. These relations are applied to the selection rules for absorption of circularly polarized light for a helical polymer in a magnetostatic field, and employed to derive expressions for the total distribution of magnetic and natural ellipticity over the exciton band. The modifications required to facilitate application to small molecular systems are outlined.