Stokes Mueller Treatment of Artifacts in Natural Raman Optical Activity

Abstract

A description of Raman scattering based on the theory by Barron and on Stokes Mueller formalism was developed into a uniform mathematical calculus such that Raman scattering can now be easily represented by a simple phenomenological matrix. This matrix, the Mueller matrix of a modulator driven by a square-wave voltage, and the matrix for a laser regarded as a fictitious polarizer are presented for the first time. With the use of these three matrices and the ones for the analyzer, the polarizer, the linearly birefringent sample cell, the circularly birefringent sample, and the partially polarizing detector, the main reasons for the appearance of artifacts in Raman optical activity have been identified. On the basis of a calculation for right-angle scattering of an isotropic solution of chiral molecules, sources of artifacts appear to be the linear birefringence of the cell walls and of the modulator material. Phase-sensitive detection is found to observe Raman optical activity with a minimal number of artifacts.