Anomalously large isotope effect in the glass transition of water.
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ABSTRACT:
SUBMITTER: Gainaru C
PROVIDER: S-EPMC4267340 | biostudies-literature | 2014 Dec
REPOSITORIES: biostudies-literature
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Anomalously large isotope effect in the glass transition of water.
Gainaru Catalin C Agapov Alexander L AL Fuentes-Landete Violeta V Amann-Winkel Katrin K Nelson Helge H Köster Karsten W KW Kolesnikov Alexander I AI Novikov Vladimir N VN Richert Ranko R Böhmer Roland R Loerting Thomas T Sokolov Alexei P AP
Proceedings of the National Academy of Sciences of the United States of America 20141124 49
We present the discovery of an unusually large isotope effect in the structural relaxation and the glass transition temperature Tg of water. Dielectric relaxation spectroscopy of low-density as well as of vapor-deposited amorphous water reveal Tg differences of 10 ± 2 K between H2O and D2O, sharply contrasting with other hydrogen-bonded liquids for which H/D exchange increases Tg by typically less than 1 K. We show that the large isotope effect and the unusual variation of relaxation times in wa ...[more]
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