The onset of intramolecular vibrational energy redistribution and its intermediate case: The ν1 and 2ν1 molecular beam, optothermal spectra of trifluoropropyne

摘要: Using the optothermal method for molecular beam, infrared spectroscopy, we have measured both fundamental and first overtone of acetylenic C–H stretch in CF3CCH. In observe a spectrum which shows only few perturbations. The majority lines can be successfully fit to model assuming an anharmonic coupling single, near‐resonant background state with matrix element 0.006 cm−1. We observed other perturbations this spectrum, including coupled by weak perpendicular Coriolis interaction. All couplings are very local nature. overtone, where density states increases factor 100, characteristic system intermediate case IVR (intramolecular vibrational energy redistribution). Analysis R(0) P(1) transitions provides homogeneous lifetime about 2 ns, is long compared lifetimes generally quoted ...