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Single vibronic level fluorescence spectroscopy and lifetime measurements were used to study intramolecular vibrational energy transfer in low pressure gas samples of 1B2 aniline, induced by collisions with H2O and CH3F. Overall rates of depopulation of the initially prepared levels, as well as rate constants for specific mode-to-mode transfers, have been measured for the initially excited levels 00, 10b1, and I1. The observed rates and patterns of energy transfer show both a high collisional efficiency for these polyatomic colliders and mode-to-mode specificity; they also indicate that hydrogen bonding interactions are unimportant.

SVL fluorescence spectroscopy of 1B1 difluorodiazirine is used to confirm previously measured vibrational frequencies and to allow measurement of collision induced vibrational redistribution in 1B1 difluorodiazirine. The latter is found to have the following properties: (i) The cross section is large, of the order of one percent of the hard sphere collision cross section; (ii) The observed mode-to-mode energy transfer is very selective; (iii) The pathways for energy exchange appear not to be influenced by the symmetries of the initial and final levels; (iv) The data are qualitatively consistent with the predictions of the McDonald–Rice model, but not with the Parmenter–Tang rules.