15min:

T. D. JAEGER AND M. A. DUNCAN, University of Georgia, Department of Chemistry, Athens, GA, 30602-2556.

First row transition metal ion-benzene complexes of the form M⁺(benzene) _x and M⁺(benzene) _x Ar are produced by laser vaporization in a pulsed nozzle source, mass-selected in a time of flight mass spectrometer and excited in the infrared with an OPO/OPA laser system. Multiphoton dissociation occurs by the elimination of whole benzene molecules or argon. The photofragment yield versus wavelength produces IR resonance-enhanced multiphoton photodissociation (IR-REMPD) spectra for these complexes. Vibrational bands observed in the 2700-3300 cm^-1 region correspond to vibrational modes in the benzene molecules but are shifted from those of free benzene due to the interaction with the metal ion.