Pitt Logo LinkContact Us

Infrared Spectroscopy of Small Protonated Water Clusters, H(+)(H2O)n (n = 2-5): Isomers, Argon Tagging, and Deuteration.

Douberly, G E and Walters, R S and Cui, J and Jordan, Kenneth D and Duncan, M A (2010) Infrared Spectroscopy of Small Protonated Water Clusters, H(+)(H2O)n (n = 2-5): Isomers, Argon Tagging, and Deuteration. The Journal of Physical Chemistry. A, 114 (13). pp. 4570-4579. ISSN 1089-5639

Permission to view external content may be subject to publisher's access restrictions.
Official URL: http://dx.doi.org/10.1021/jp100778s

Abstract

Infrared photodissociation spectroscopy is reported for mass-selected H(+)(H(2)O)(n) complexes and their deuterated analogues with and without argon "tagging." H(+)(H(2)O)(n)Ar(m) and D(+)(D(2)O)(n)Ar(m) complexes are studied in the O-H (O-D) stretching region for clusters in the small size range (n = 2-5). Upon infrared excitation, these clusters fragment by the loss of either argon atoms or one or more intact water molecules. Their excitation spectra show distinct bands in the region of the symmetric and asymmetric stretches of water and in the hydrogen bonding region. Experimental studies are complemented by computational work that explores the isomeric structures, their energetics and vibrational spectra. The addition of an argon atom is essential to obtain photodissociation for the n = 2-3 complexes, and specific inclusion of the argon in calculations is necessary to reproduce the measured spectra. For n = 3-5, spectra are obtained both with and without argon. The added argon atom allows selection of a subset of colder clusters and it increases the photodissociation yield. Although most of these clusters have more than one possible isomeric structure, the spectra measured correspond to a single isomer that is computed to be the most stable. Deuteration in these small cluster sizes leads to expected lowering of frequencies, but the spectra indicate the presence of the same single most-stable isomer for each cluster size.


Share

Citation/Export:
Social Networking:

Details

Item Type: Article
Creators/Authors:
CreatorsEmailORCID
Douberly, G E
Walters, R S
Cui, J
Jordan, Kenneth Djordan@pitt.edu
Duncan, M A
Title: Infrared Spectroscopy of Small Protonated Water Clusters, H(+)(H2O)n (n = 2-5): Isomers, Argon Tagging, and Deuteration.
Status: Published
Abstract: Infrared photodissociation spectroscopy is reported for mass-selected H(+)(H(2)O)(n) complexes and their deuterated analogues with and without argon "tagging." H(+)(H(2)O)(n)Ar(m) and D(+)(D(2)O)(n)Ar(m) complexes are studied in the O-H (O-D) stretching region for clusters in the small size range (n = 2-5). Upon infrared excitation, these clusters fragment by the loss of either argon atoms or one or more intact water molecules. Their excitation spectra show distinct bands in the region of the symmetric and asymmetric stretches of water and in the hydrogen bonding region. Experimental studies are complemented by computational work that explores the isomeric structures, their energetics and vibrational spectra. The addition of an argon atom is essential to obtain photodissociation for the n = 2-3 complexes, and specific inclusion of the argon in calculations is necessary to reproduce the measured spectra. For n = 3-5, spectra are obtained both with and without argon. The added argon atom allows selection of a subset of colder clusters and it increases the photodissociation yield. Although most of these clusters have more than one possible isomeric structure, the spectra measured correspond to a single isomer that is computed to be the most stable. Deuteration in these small cluster sizes leads to expected lowering of frequencies, but the spectra indicate the presence of the same single most-stable isomer for each cluster size.
Date: 08 April 2010
Date Type: Publication
Journal or Publication Title: The Journal of Physical Chemistry. A
Volume: 114
Number: 13
Publisher: American Chemical Society
Page Range: pp. 4570-4579
DOI or Unique Handle: 10.1021/jp100778s
Refereed: Yes
ISSN: 1089-5639
Official URL: http://dx.doi.org/10.1021/jp100778s
Article Type: Research Article
Schools and Programs: Dietrich School of Arts and Sciences > Chemistry
Date Deposited: 12 Nov 2012 09:56
Last Modified: 12 Nov 2012 09:56
MeSH Headings: Argon--chemistry; Binding Sites; Computational Biology; Deuterium--chemistry; Hydrogen Bonding; Isomerism; Photochemistry; Protons; Spectrophotometry, Infrared; Thermodynamics; Water--chemistry
PubMed ID: 20232806

Actions (login required)

View Item