Cavity ring-down polarimetry (CRDP): theoretical and experimental characterization

Abstract

Detailed theoretical analyses are presented for cavity ring-down polarimetry, a recently developed scheme for probing circular birefringence (nonresonant rotatory dispersion) and circular dichroism (resonant differential absorption) with unprecedented sensitivity. Aside from elucidating the nature of time-resolved signals generated by various modes of operation, the influence of instrumental imperfections on polarimetric response is examined. The unique ability of cavity ring-down polarimetry to interrogate nonresonant optical activity in low-pressure chiral vapors is demonstrated by extracting specific rotation parameters at two complementary excitation wavelengths (355 nm and 633 nm) for gaseous samples of α-pinene, β-pinene, and cis-pinane. The resulting isolated-molecule properties are contrasted with those derived from conventional solution-phase experiments and state-of-the-art ab initio calculations.