Pyridine radical cation and its fluorine substituted derivatives

Abstract

The spectra and relaxation of the pyridine cation and of several of its fluorinated derivatives are studied in low temperature Ne matrices. The ions are generated by direct photoionization of the parent compounds. Of the compounds studied, laser induced B̃→X̃ and B̃→Ã fluorescence is observed only for the 2,6-difluoropyridine cation. The analysis of the spectrum indicates that the ion is planar both in the X̃ and B̃ states. The large variety in the spectroscopic and relaxation behavior of fluoropyridine radical cations is explained in terms of their electronic structure and of the differential shifts of the individual electronic states caused by the fluorine substitution. © 1982 American Institute of Physics.