Laser-induced fluorescence study of the reactions Cu+X2→CuX+X (X=F, Cl, Br, and I)

Abstract

Reactions of a beam of Cu with halogen gases at low pressure have been studied in the single‐collision regime using a pulsed tunable dye laser to excite the ground electronic state products to fluorescing states. CuF vibrational state populations could be estimated up to v=25, but for the heavier halides information on only v≤3 was obtainable from the excitation spectra. The vibrational distributions are similar to prior expectations but somewhat colder. Spectral simulations also reveal that the fraction of energy available to products appearing as rotation is considerably below prior predictions. This pattern of energy release may be related to product repulsion, which occurs as the products transform from a strongly bound XCuX intermediate to the singly ionic ground state molecule plus halogen atom.