The laser photoelectron spectrum of gas phasephyphen;difluorobenzene

摘要

Gas phasephyphen;difluorobenzene (PDFB) has been laser ionized from several vibronic levels of its1B2ufirst excited electronic state. The vibrational state distribution of the ions generated depends on the vibronic level from which ionization occurs. The fundamental frequencies of five symmetric vibrations; ngr;2, ngr;3, ngr;4, ngr;5, and ngr;6, and three asymmetric vibrations; ngr;8, ngr;29, and ngr;30, of the lowest electronic state of PDFB+have been assigned. Effects due to electronic configuration interaction are observed in the photoelectron spectra. Small peaks are also observed in the spectra which may reflect a change in geometry of the ground state cation.