Polarized raman optical activity and the bond polarizability model

Abstract

We show that, within a simple version of the bond polarizability model based on the approximation of axially-symmetric bonds, the polarized Raman optical activity is simply double the depolarized in a given band. Many of the bands in preliminary polarized and depolarized Raman optical activity spectra obtained with a new optical multichannel instrument accord with this result, which indicates that this and related models provide a useful starting point for interpreting ROA spectra in terms of structural detail. Additionally, our spectra imply that isotropic contributions can usually be neglected in most Raman optical activity bands, but that electric quadrupole contributions, while smaller than magnetic dipole contributions, are still usually significant.