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Infrared Spectroscopy Of Large Protonated Water Clusters H+(H2O) n (n ≤ 221)

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Spectroscopic Investigations of Hydrogen Bond Network Structures in Water Clusters

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Abstract

In studying large-scale hydrogen-bonded water network structures, we have succeeded in measuring the IR spectra of the precisely size-selected protonated water clusters H+(H2O) n up to the hitherto uncovered size of n = 221. In IR spectra, we identified the 4-coordinated and 3-coordinated water bands. We also showed that the abundance of 4-coordinated waters gradually increases with increasing cluster size. In the interior of the clusters, as has been seen in the size-averaged (H2O)<n> studies, the implication of network ordering (crystallization) was observed. The free OH frequency suggests that the surface structures of the large-sized clusters are similar to those of liquid water and ice. The observed spectra, in addition to recently reported spectra for large water clusters, are expected to be a benchmark for studies concerning large-scale hydrogen-bonded networks involving hundreds of water molecules.

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  1. Institute for Molecular Science, Photo-Molecular Science I, National Institutes of Natural Sciences, 38 Nishigo-Naka, Myodaiji, Okazaki, 444-8585, Japan

    Kenta Mizuse

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Mizuse, K. (2013). Infrared Spectroscopy Of Large Protonated Water Clusters H+(H2O) n (n ≤ 221). In: Spectroscopic Investigations of Hydrogen Bond Network Structures in Water Clusters. Springer Theses. Springer, Tokyo. https://doi.org/10.1007/978-4-431-54312-1_3

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