Circular dichroism: A general theory based on quantum electrodynamics

Abstract

A theory of circular dichroism is developed through a direct calculation of the absorption rates for circularly polarized light on molecules. From this a differential rate as between left and right circularly polarized light is calculated. This is immediately related to the experimental data on circular dichroism. When the calculations are restricted to the dipole approximation we reproduce the rotatory strength in the form of a differential Einstein B coefficient. Higher moments are considered in detail and their effects analyzed for both the locked‐in situation and the case of randomly oriented molecular absorbers. A general expression is obtained for the differential absorption rate.