Photoelectron imaging and theoretical study on nascent hydrogen bond network in microsolvated clusters of Au- (CH3OH)n (n = 1-5).

We first demonstrate the photoelectron spectroscopic evidence of the transition of two competitive solvation patterns in the Au-(CH3OH)(n) (n = 1-5) clusters. Quantum chemical calculations have been carried out to characterize the geometric structures, energy properties and hydrogen-bonded patterns, and to aid the spectral assignment. It has been found that the nonconventional hydrogen bonds dominate the small clusters (n = 1 and 2), whereas the conventional hydrogen bonds play more and more important role from n = 2 to n = 5. This finding provides concrete hydrogen bond network evolution of Au- surrounded by methanol molecules.