title: Ultraviolet and infrared photodissociation of Si(+)(C6H6)n and Si(+)(C6H6)(n)Ar clusters.
abstract: Ion-molecule complexes of the form Si(+)(C6H6)n and Si(+)(C6H6)(n)Ar are produced by laser vaporization in a pulsed nozzle cluster source. These clusters are mass-selected and studied with ultraviolet (355 nm) photodissociation and resonance-enhanced infrared photodissociation spectroscopy in the C-H stretch region of benzene. In the UV, Si(+)(C6H6)n clusters (n = 1-5) fragment to produce the Si(+)(C6H6)n mono-ligand species, suggesting that this ion has enhanced relative stability. IR photodissociation of Si(+)(C6H6)n complexes occurs by the elimination of benzene, while Si(+)(C6H6)(n)Ar complexes lose Ar. Resonances reveal C-H vibrational bands in the 2900-3300 cm(-1) region characteristic of the benzene ligand with shifts caused by the silicon cation bonding. The IR spectra confirm that the major component of the Si(+)(C6H6)n ions studied have the pi-complex structure rather than the isomeric insertion products suggested previously.
authors.affiliation: Department of Chemistry, University of Georgia, Athens, Georgia 30602-2556, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Jaeger
authors.forename: E D
authors.initials: ED
authors.lastname: Pillai
authors.forename: T D
authors.initials: TD
authors.lastname: Jaeger
authors.forename: M A
authors.initials: MA
authors.lastname: Duncan