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Title: A surprisingly simple correlation between the classical and quantum structural networks in liquid water

Abstract

Nuclear quantum effects in liquid water have profound implications for several of its macroscopic properties related to structure, dynamics, spectroscopy and transport. Although several of water’s macroscopic properties can be reproduced by classical descriptions of the nuclei using potentials effectively parameterized for a narrow range of its phase diagram, a proper account of the nuclear quantum effects is required in order to ensure that the underlying molecular interactions are transferable across a wide temperature range covering different regions of that diagram. When performing an analysis of the hydrogen bonded structural networks in liquid water resulting from the classical (class.) and quantum (q.m.) descriptions of the nuclei with the transferable, flexible, polarizable TTM3-F interaction potential, we found that the two results can be superimposed over the temperature range of T=270-350 K using a surprisingly simple, linear scaling of the two temperatures according to T(q.m.)=aT(class)- T , where a=1.2 and T=51 K. The linear scaling and constant shift of the temperature scale can be considered as a generalization of the previously reported temperature shifts (corresponding to structural changes and the melting T) induced by quantum effects in liquid water.

Authors:
ORCiD logo; ; ORCiD logo
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1378011
Report Number(s):
PNNL-SA-95712
Journal ID: ISSN 0021-9606; KC0301050
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 147; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Hamm, Peter, Fanourgakis, George S., and Xantheas, Sotiris S.. A surprisingly simple correlation between the classical and quantum structural networks in liquid water. United States: N. p., 2017. Web. doi:10.1063/1.4993166.
Hamm, Peter, Fanourgakis, George S., & Xantheas, Sotiris S.. A surprisingly simple correlation between the classical and quantum structural networks in liquid water. United States. doi:10.1063/1.4993166.
Hamm, Peter, Fanourgakis, George S., and Xantheas, Sotiris S.. 2017. "A surprisingly simple correlation between the classical and quantum structural networks in liquid water". United States. doi:10.1063/1.4993166.
@article{osti_1378011,
title = {A surprisingly simple correlation between the classical and quantum structural networks in liquid water},
author = {Hamm, Peter and Fanourgakis, George S. and Xantheas, Sotiris S.},
abstractNote = {Nuclear quantum effects in liquid water have profound implications for several of its macroscopic properties related to structure, dynamics, spectroscopy and transport. Although several of water’s macroscopic properties can be reproduced by classical descriptions of the nuclei using potentials effectively parameterized for a narrow range of its phase diagram, a proper account of the nuclear quantum effects is required in order to ensure that the underlying molecular interactions are transferable across a wide temperature range covering different regions of that diagram. When performing an analysis of the hydrogen bonded structural networks in liquid water resulting from the classical (class.) and quantum (q.m.) descriptions of the nuclei with the transferable, flexible, polarizable TTM3-F interaction potential, we found that the two results can be superimposed over the temperature range of T=270-350 K using a surprisingly simple, linear scaling of the two temperatures according to T(q.m.)=aT(class)- T , where a=1.2 and T=51 K. The linear scaling and constant shift of the temperature scale can be considered as a generalization of the previously reported temperature shifts (corresponding to structural changes and the melting T) induced by quantum effects in liquid water.},
doi = {10.1063/1.4993166},
journal = {Journal of Chemical Physics},
number = 6,
volume = 147,
place = {United States},
year = 2017,
month = 8
}
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