Symmetry Rules for Optical Rotation

It is shown that to produce optical rotation in a chromophore, a potential function must have the symmetry properties of a pseudoscalar in the symmetry group of the unperturbed chromophore. It is thus possible to establish regional rules of optical rotation without recourse to particular models and assumptions of the electronic states of the chromophore. Formulas and geometric representations of the resulting regional rules are given for a number of symmetries which are encountered in molecular problems. The results are not applicable to coupled oscillator models of optical rotation.