Geometry of the magic number H+(H2O)21 water cluster by proxy. Issue 7 (26th January 2015)

• Record Type: Journal Article
• Authors: Ryding, Mauritz Johan; Izsák, Róbert; Merlot, Patrick; Reine, Simen; Helgaker, Trygve; Uggerud, Einar
• Is Part Of: Physical chemistry chemical physics. Volume 17:Issue 7(2015)
• Page Start: 5466
• Page End: 5473
• Publication Date: 2015-01-26
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c4cp05246c
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Substituting H2 O with tert -butanol allows for the experimental determination of the number of dangling hydrogen bonds in the H + (H2 O)21 cluster. Abstract : Abundance mass spectra, obtained upon carefully electrospraying solutions of tert -butanol (TB) in water into a mass spectrometer, display a systematic series of peaks due to mixed H + (TB) m (H2 O) n clusters. Clusters with m + n = 21 have higher abundance (magic number peaks) than their neighbours when m ≤ 9, while for m > 9 they have lower abundance. This indicates that the mixed TB–H2 O clusters retain a core hydrogen bonded network analogous to that in the famous all-water H + (H2 O)21 cluster up to the limit m = 9. The limiting value corresponds to the number of dangling O–H groups pointing out from the surface of the degenerated pentagonal dodecahedral, considered to be the lowest energy form of H + (H2 O)21 ; the experimental findings therefore support this geometry. The experimental findings are supported by ab initio quantum chemical calculations to provide a consistent framework for the interpretation of these kinds of experiments.