INFRARED, RAMAN, AND COHERENT ANTI-STOKES-RAMAN SPECTROSCOPY OF THE HYDROGEN-DEUTERIUM ISOTOPOMERS OF NITROMETHANE

The vibrational spectroscopy of the four hydrogen/deuterium isotopomers of nitromethane was investigated. Infrared, Raman, and coherent anti-Stokes Raman spectroscopy (CARS) of the isotopomers were used to determine vibrational frequencies for each isotopomer. Results for the d0, d2, and d3 isotopomers agree well with literature values. Gas- and liquid-phase spectra for the d1 isotopomer are presented, and the measured vibrational frequencies compare well with a theoretical prediction. In addition, high-resolution Raman spectra of the CN stretch mode were used to analyze the elements of the anharmonic coupling matrix involving this mode. Finally, the relative differential Raman scattering cross section of the CN stretch mode of each isotopomer was determined.