Long range influence of an excess proton on the architecture of the hydrogen bond network in large-sized water clusters.

Infrared spectra of completely size-selected protonated water clusters H+(H2O)n are reported for clusters ranging from n=15 to 100. The behavior of the dangling OH stretch bands shows that the hydrogen bond structure in H+(H2O)n is uniquely different to that of (H2O)n up to the size of n=100, at least. This finding indicates that the presence of an excess proton creates a characteristic morphology in the hydrogen bond network architecture of more than 100 surrounding water molecules.