VIBRATION WAVE-NUMBERS OF 4-AMINOBENZOTRIFLUORIDE IN THE GROUND AND S1 ELECTRONIC STATES FROM ITS SUPERSONIC JET S1-S0 FLUORESCENCE, INFRARED, AND RAMAN-SPECTRA

Single vibronic level fluorescence (SVLF) spectra, in a supersonic jet, and infrared and Raman spectra of 4-aminobenzotrifluoride have been recorded and assigned to give, apart from some a2 vibrations, a complete set of fundamental vibration wavenumbers in the S0 electronic state. A supersonic jet fluorescence excitation spectrum has given some of the lower vibration wavenumbers in the S1 electronic state. Observation of the I20, NH2-inversion band in the SVLF spectrum agrees with the interpretation of the far infrared spectrum. Several CF3 torsional levels in S0 are populated, even in the supersonic jet, and one result of this is to allow the observation of vibrations which are of b1 symmetry in the C2v point group and which would be forbidden in the rigid molecule. © 1991.