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Title: The structures of interstitial hydrogen centers in VO 2 in the dilute limit from their vibrational properties and theory

Abstract

The introduction of a large concentration of H into VO 2 is known to suppress the insulating phase of the metal-insulator transition that occurs upon cooling below 340 K. We have used infrared spectroscopy and complementary theory to study the properties of interstitial H and D in VO 2 in the dilute limit to determine the vibrational frequencies, thermal stabilities, and equilibrium positions of isolated interstitial H and D centers. The vibrational lines of several OH and OD centers were observed to have thermal stabilities similar to that of the hydrogen that suppresses the insulating phase. Theory associates two of the four possible OH configurations for Hi in the insulating VO 2 monoclinic phase with OH lines seen by experiment. Furthermore, theory predicts the energies and vibrational frequencies for configurations with Hi trapped near a substitutional impurity and suggests such defects as candidates for additional OH centers that have been observed.

Authors:
 [1];  [1];  [1];  [1];  [2]
  1. Lehigh Univ., Bethlehem, PA (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1286942
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Physics. Condensed Matter
Additional Journal Information:
Journal Volume: 28; Journal Issue: 39; Journal ID: ISSN 0953-8984
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Yin, W., Qin, Ying, Fowler, W. B., Stavola, M., and Boatner, Lynn A.. The structures of interstitial hydrogen centers in VO2 in the dilute limit from their vibrational properties and theory. United States: N. p., 2016. Web. doi:10.1088/0953-8984/28/39/395401.
Yin, W., Qin, Ying, Fowler, W. B., Stavola, M., & Boatner, Lynn A.. The structures of interstitial hydrogen centers in VO2 in the dilute limit from their vibrational properties and theory. United States. doi:10.1088/0953-8984/28/39/395401.
Yin, W., Qin, Ying, Fowler, W. B., Stavola, M., and Boatner, Lynn A.. 2016. "The structures of interstitial hydrogen centers in VO2 in the dilute limit from their vibrational properties and theory". United States. doi:10.1088/0953-8984/28/39/395401. https://www.osti.gov/servlets/purl/1286942.
@article{osti_1286942,
title = {The structures of interstitial hydrogen centers in VO2 in the dilute limit from their vibrational properties and theory},
author = {Yin, W. and Qin, Ying and Fowler, W. B. and Stavola, M. and Boatner, Lynn A.},
abstractNote = {The introduction of a large concentration of H into VO2 is known to suppress the insulating phase of the metal-insulator transition that occurs upon cooling below 340 K. We have used infrared spectroscopy and complementary theory to study the properties of interstitial H and D in VO2 in the dilute limit to determine the vibrational frequencies, thermal stabilities, and equilibrium positions of isolated interstitial H and D centers. The vibrational lines of several OH and OD centers were observed to have thermal stabilities similar to that of the hydrogen that suppresses the insulating phase. Theory associates two of the four possible OH configurations for Hi in the insulating VO2 monoclinic phase with OH lines seen by experiment. Furthermore, theory predicts the energies and vibrational frequencies for configurations with Hi trapped near a substitutional impurity and suggests such defects as candidates for additional OH centers that have been observed.},
doi = {10.1088/0953-8984/28/39/395401},
journal = {Journal of Physics. Condensed Matter},
number = 39,
volume = 28,
place = {United States},
year = 2016,
month = 7
}

Journal Article:
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