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Updated: Jul 19, 2026

Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
Infrared signature of structures associated with the H+(H2O)n (n = 6 to 27) clusters
J-W Shin1, N I Hammer, E G Diken
1Sterling Chemistry Laboratory, Yale University, Post Office Box 208107, New Haven, CT 06520, USA.
Abstract:
We report the OH stretching vibrational spectra of size-selected H+(H2O)n clusters through the region of the pronounced "magic number" at n = 21 in the cluster distribution. Sharp features are observed in the spectra and assigned to excitation of the dangling OH groups throughout the size range 6 = n = 27. A multiplet of such bands appears at small cluster sizes. This pattern simplifies to a doublet at n = 11, with the doublet persisting up to n = 20, but then collapsing to a single line in the n = 21 and n = 22 clusters and reemerging at n = 23. This spectral simplification provides direct evidence that, for the magic number cluster, all the dangling OH groups arise from water molecules in similar binding sites.
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