METAL CLUSTER CATION REACTIONS - CARBON-MONOXIDE ASSOCIATION TO CU-N+ IONS

Copper cluster cations (Cun+ ,n = 1-14) were produced in a laser vaporization/flow tube apparatus and equilibrated to room temperature. The association rate constants of carbon monoxide onto these ions were measured; low-pressure, termolecular behavior was observed for the smaller species while for clusters greater than Cu7+, the longer lifetimes due to the increased number of degrees of freedom leads to pressure independence (> 0.3 Torr) of the effective bimolecular rates. Unimolecular decay theory (RRKM) is used to explain the overall trend and when intrinsic surface site reactivity is taken into account, excellent agreement with measured reactivity is obtained. © 1990 American Institute of Physics.