2-PHOTON PHOTOASSISTED REACTIONS OF COLLISION PAIRS CONSISTING OF XE WITH HALOGEN-CONTAINING POLYATOMIC-MOLECULES

Excitation spectra have been acquired for the two-photon, laser-assist ed reactions between collision pairs of Xe with CCl4, CCl3Br, CH3I, CH 2I2, CH2ICl, and SOCl2. In each case the product of the reaction is Xe X(B,C); X = halogen. The excitation spectra obtained at 300 K in 100 T orr of Xe and 1.3 Torr of reagent have thresholds near 255 nm and incr ease toward shorter wavelength. Unexpected resonance-like features hav e been found in the excitation spectra of Xe/CH2ICl and Xe/CCl3Br. A s et of relative two-photon excitation rates was obtained at 238 and 227 nm for all pairs by comparison to CCl4, which was selected as a stand ard. The excitation spectra for the polyatomic molecular pairs can be compared to previously published excitation spectra of diatomic haloge n molecules with Xe. The two-photon, laser-assisted reaction of the Xe .F2 van der Waals molecule prepared by free-jet expansion also is repo rted.