Photodynamics within (CH3OH)nCr(CO)6 Heteroclusters: Observation of an Isotope Effect.

摘要

We have recently examined the multiphoton dissociation and ionization dynamics of mixed van der Waals heteroclusters of Cr(CO)6 solvated by methanol, and have inferred from photoion fragmentation branching ratios that CD30D is more efficient than CH3OH in relaxing excess internal energy of the nascent photoion via intracluster energy transfer. Multiphoton ionization is suggested to proceed via single-photon photodissociation of the solvated Cr(CO)6, followed by two-photon ionization of the coordinatively unsaturated photoproduct. Excess energy in the internal modes of the nascent photoion appears to be disposed of via non-statistical, mode-specific transfer to the internal degrees of freedom of an adjacent solvent molecule within the cluster. Photoionization using laser power densities on the order of 1012 to 1013 W/cm2 is accompanied by extensive intracluster bimolecular chemistry.