Anomalously large isotope effect in the glass transition of water
- Dortmund Univ. of Technology (Germany). Dept. of Physics
- Univ. of Tennessee, Knoxville, TN (United States). Joint Inst. for Neutron Sciences, Dept. of Chemistry; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Science Division
- Univ. of Innsbruck, Innsbruck (Austria). Inst. of Physical Chemistry
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical and Engineering Materials Division
- Arizona State Univ., Tempe, AZ (United States). Dept. of Chemistry and Biochemistry
Here 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±2K between H2O and D2O, sharply contrasting with other hydrogen bonded liquids for which H/D exchange increases Tg by typically less than 1K. We show that the large isotope effect and the unusual variation of relaxation times in water at low temperatures can be explained in terms of quantum effects. Thus, our findings shed new light on water's peculiar low-temperature dynamics and the possible role of quantum effects in its structural relaxation, and possibly in dynamics of other low molecular weight liquids.
- Research Organization:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)
- Grant/Contract Number:
- AC05-00OR22725; CHE-1213444; CHE-1026124; BO1301
- OSTI ID:
- 1286807
- Journal Information:
- Proceedings of the National Academy of Sciences of the United States of America, Vol. 111, Issue 49; ISSN 0027-8424
- Publisher:
- National Academy of Sciences, Washington, DC (United States)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
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