Observation of rovibrational dephasing of molecules in parahydrogen crystals by frequency domain spectroscopy
Rotation-vibration transitions of methane molecules embedded in parahydrogen crystals were investigated through Fourier transform infrared spectroscopy. Each transition shows extremely sharp peaks with a Lorentzian line shape profile, which indicates the spectra are free from inhomogeneous broadening. The steep temperature dependence of the linewidths observed in the range between 3.7 and 8. 5 K is interpreted to be a result of the pure dephasing relaxation mechanism. A remarkable difference in population relaxation widths between stretching and bending vibrational excited states was also found.
Katsuki
H
Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan and and Japan Science and Technology Corporation (JST), Kyoto 606-8502, Japan.
Momose
T