Polarization dependence of vibrational coupling signals in femtosecond stimulated Raman spectroscopy

Renee R Frontiera; Richard A Mathies

doi:10.1063/1.2780843

Polarization dependence of vibrational coupling signals in femtosecond stimulated Raman spectroscopy

J Chem Phys. 2007 Sep 28;127(12):124501. doi: 10.1063/1.2780843.

Authors

Renee R Frontiera¹, Richard A Mathies

Affiliation

¹ Department of Chemistry, University of California, Berkeley, California 94720, USA.

PMID: 17902915
DOI: 10.1063/1.2780843

Abstract

The polarization dependence of vibrational coupling signals seen in femtosecond stimulated Raman spectroscopy (FSRS) is investigated. Changing the polarization of a pulse used to impulsively excite coherent low frequency chlorine bending motion in CDCl(3) has a dramatic effect on the line shape of vibrational sidebands which arise from the anharmonic coupling of the pumped modes at 262 and 365 cm(-1) with the higher frequency symmetric stretching mode at 652 cm(-1). The asymmetric bend sideband (652+262 cm(-1)) changes sign and magnitude as the impulsive pulse polarization is rotated relative to the Raman pulses, while the symmetric bend sideband (652+365 cm(-1)) is relatively polarization independent. These experiments demonstrate the ability of FSRS to obtain time-resolved information on not only the vibrational coupling strength but also the symmetry of anharmonically coupled modes.