The laser-induced fluorescence spectrum of the 1,2,3-trifluorobenzene radical cation

Laser-induced fluorescence spectra of the radical cation of 1,2,3-trifluorobenzene have determined the origin of the electronic transition and the lifetime of the excited state in both the gas phase and solid Ne matrices. The gas phase spectrum shows relatively poorly resolved vibrational structure, as the lines seem to be badly broadened by rotational contours. The matrix spectra show extensive, well-resolved vibrational structure with small but noticeable matrix perturbations. The structure is also rather irregular and differs considerably between the ground and excited states. All of these observations are consistent with a considerable change in geometry between the two electronic states.