15min:

ILIAS SIOUTIS, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, Columbus, OH 43210; VADIM L. STAKHURSKY, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, Columbus, OH 43210; GYÖRGY TARCZAY, Department of General and Inorganic Chemistry, Eötvös University, P. O. Box 32, H-1518 Budapest 112, Hungary; AND TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, Columbus, OH 43210.

The tropyl radical (C₇H₇) has been proposed to be a possible intermediate in the decay of the benzyl radical following similar pathways of isomerization to the ones between their cationic forms. Besides the fact that very little is known about such reactions, tropyl has also received considerable theoretical attention, since the doubly degenerate ground X²E₂'' and excited A²E₃'' D_7h electronic states exhibit Jahn-Teller (JT) activity. To gain further insight about the molecule's vibrational properties, the laser-induced fluorescence (LIF) spectroscopy was combined with supersonic free jet expansion techniques to record the wavelength dispersed fluorescence (DF) spectra of tropyl. The DF emission was collected by pumping different vibronic bands of the A²E₃'' X²E₂'' LIF excitation spectrum. An analysis reveals significant Jahn-Teller activity in 4 e₃' modes for the X²E₂'' state and 3 e₁' modes for the A²E₃'' and provides values for their deperturbed vibrational frequencies as well as their linear Jahn-Teller constants. The experimental observations and intensity simulations for the observed emission traces will be presented and discussed.