High resolution infrared and Raman spectroscopy of ν2 and associated combination and hot bands of 13C12CD2

Infrared and Raman spectra of dideuterated acetylene containing one 13C atom, 13C12CD2, have been recorded and analysed to obtain detailed information on the fundamental 2 band and associated combination and hot bands. Infrared spectra were recorded at 4103cm1 resolution in the region 11502900cm1, which contains combination and hot bands from the ground and the bending v4¼1 and v5¼1 states. The Q-branches of the 2 fundamental and associated hot bands (2þ44, 2þ55, 2þ2424, 2þ2525 and 2þ4þ5(4þ5)) were recorded using inverse Raman spectroscopy, with an instrumental resolution of about 3103cm1. In addition, the observation of the 222 Raman band was carried out populating the v2¼1 state by stimulated Raman pumping. In total, 11 Raman and 9 infrared bands were analysed, involving all the l-vibrational components of the excited stretchingbending manifolds up to vt¼v4þv5¼2. A simultaneous analysis of all infrared and Raman assigned transitions has been performed on the basis of a theoretical model which takes into account the rotation and vibration l-type resonances within each vibrational manifold and the DarlingDennison anharmonic resonance between the 2þ24 and 2þ25 states. The parameters obtained reproduce the assigned transition wavenumbers with a standard deviation of the same order of magnitude as the experimental uncertainty.