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Title: Infrared spectroscopy of water clusters isolated in methane matrices: Effects of isotope substitution and annealing

Abstract

Using infrared-active solvents of CH{sub 4} and CD{sub 4} for matrix isolation, we measured infrared spectra of H{sub 2}O and D{sub 2}O clusters at 7 K. The solute-concentration dependence of the spectrum of H{sub 2}O clusters in a CH{sub 4} matrix was investigated and was used for the peak assignment. Annealing procedures were found to promote the size growth of water clusters in methane matrices for all the combinations of (H{sub 2}O, CH{sub 4}), (H{sub 2}O, CD{sub 4}), (D{sub 2}O, CH{sub 4}), and (D{sub 2}O, CD{sub 4}). We also monitored the ν{sub 3} absorption due to methane to find the annealing-induced structural change only of solid CH{sub 4}. The matrix effects on the vibrations of the clusters are discussed on the basis of “T{sub c} plots”, where their frequencies are plotted as a function of the square root of the matrix critical temperature, T{sub c}. The obtained plots assure the validity of the assignment of the cluster peaks.

Authors:
; ; ;  [1]
  1. Department of Physics, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588 (Japan)
Publication Date:
OSTI Identifier:
22611489
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION; ABSORPTION SPECTROSCOPY; ALLOCATIONS; ANNEALING; CONCENTRATION RATIO; CRITICAL TEMPERATURE; HEAVY WATER; INFRARED SPECTRA; ISOTOPES; MATRIX ISOLATION; METHANE; MOLECULAR CLUSTERS; SOLIDS; SOLVENTS; TEMPERATURE RANGE 0000-0013 K; WATER

Citation Formats

Yamakawa, Koichiro, E-mail: koichiro.yamakawa@gakushuin.ac.jp, Ehara, Namika, Ozawa, Nozomi, and Arakawa, Ichiro. Infrared spectroscopy of water clusters isolated in methane matrices: Effects of isotope substitution and annealing. United States: N. p., 2016. Web. doi:10.1063/1.4958329.
Yamakawa, Koichiro, E-mail: koichiro.yamakawa@gakushuin.ac.jp, Ehara, Namika, Ozawa, Nozomi, & Arakawa, Ichiro. Infrared spectroscopy of water clusters isolated in methane matrices: Effects of isotope substitution and annealing. United States. doi:10.1063/1.4958329.
Yamakawa, Koichiro, E-mail: koichiro.yamakawa@gakushuin.ac.jp, Ehara, Namika, Ozawa, Nozomi, and Arakawa, Ichiro. 2016. "Infrared spectroscopy of water clusters isolated in methane matrices: Effects of isotope substitution and annealing". United States. doi:10.1063/1.4958329.
@article{osti_22611489,
title = {Infrared spectroscopy of water clusters isolated in methane matrices: Effects of isotope substitution and annealing},
author = {Yamakawa, Koichiro, E-mail: koichiro.yamakawa@gakushuin.ac.jp and Ehara, Namika and Ozawa, Nozomi and Arakawa, Ichiro},
abstractNote = {Using infrared-active solvents of CH{sub 4} and CD{sub 4} for matrix isolation, we measured infrared spectra of H{sub 2}O and D{sub 2}O clusters at 7 K. The solute-concentration dependence of the spectrum of H{sub 2}O clusters in a CH{sub 4} matrix was investigated and was used for the peak assignment. Annealing procedures were found to promote the size growth of water clusters in methane matrices for all the combinations of (H{sub 2}O, CH{sub 4}), (H{sub 2}O, CD{sub 4}), (D{sub 2}O, CH{sub 4}), and (D{sub 2}O, CD{sub 4}). We also monitored the ν{sub 3} absorption due to methane to find the annealing-induced structural change only of solid CH{sub 4}. The matrix effects on the vibrations of the clusters are discussed on the basis of “T{sub c} plots”, where their frequencies are plotted as a function of the square root of the matrix critical temperature, T{sub c}. The obtained plots assure the validity of the assignment of the cluster peaks.},
doi = {10.1063/1.4958329},
journal = {AIP Advances},
number = 7,
volume = 6,
place = {United States},
year = 2016,
month = 7
}
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