1 April 1990 Picosecond photochemistry in molecular clusters
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Rates of chemical reactions in molecular clusters were measured by picosecond spectroscopy in a molecular beam mass spectrometer. We report on two classes of reactions. First, we consider acid-base proton transfer from an aromatic species to a basic solvent cluster . The chemistry involving the aromatic acids aniline cation and S phenol depended strongly on the solvent type and solvent cluster size. For example phenol*(NH3)n exhibited proton transfer for n 5. The rate constant for dissociation was ka (60 10 ps)' for n = 5 - 7. A geminate recombination rate of k_a (350 lOOps)1 occurs for n = 5. No proton transfer occurred in (CH3OH) solvent cluster up to n = 11. In another class of reactions, free radical chemistry in clusters was initiated by A state excitation in (CH3I) clusters. Extensive demethylation and formation of 12 and I2(CH3I)_2 fragments occured on the order of 10 ps. A mechanism is proposed for a chain of reactions driven in part by the energy of intracluster recombination of two CH3 radicals and the elimination of ethane.
© (1990) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jack A. Syage "Picosecond photochemistry in molecular clusters", Proc. SPIE 1209, Picosecond and Femtosecond Spectroscopy from Laboratory to Real World, (1 April 1990); doi: 10.1117/12.17891; https://doi.org/10.1117/12.17891

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