Rotationally mediated vibrationndash;vibration and vibrationndash;translation energy transfer in silane

摘要

Vibrationndash;vibration (Vndash;V) and vibrationndash;translation (Vndash;T) energy transfer efficiencies have been measured for thev4=1 mode of silane in collisions with He, Ar, Kr, H2, CH4, and itself, using the timehyphen;resolved infrared doublehyphen;resonance technique. The Vndash;V cross sections are approximately onehyphen;third to onehyphen;half of the Lennardhyphen;Jones cross sections, and show a variation with the nuclearndash;spin symmetry state (A,E, orF) of the molecule. The ngr;4Vndash;T deactivation efficiencies are in the range 0.0001ndash;0.002, with the polyatomic molecules being about an order of magnitude more efficient than the noblehyphen;gas atoms. This can be quantitatively interpreted by the vibrationndash;rotation (Vndash;R) resonance transfer model of Poulsenetal. lsqb;J. Chem. Phys.58, 3381 (1973)rsqb;. A simple breathinghyphen;sphere model does not, however, provide a good representation of the Vndash;T collision efficiencies for rare gasndash;silane collisions.