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Title: The role of broken symmetry in solvation of a spherical cavity in classical and quantum water models

Abstract

Insertion of a hard sphere cavity in liquid water breaks translational symmetry and generates an electrostatic potential difference between the region near the cavity and the bulk. Here, we clarify the physical interpretation of this potential and its calculation. We also show that the electrostatic potential in the center of small, medium, and large cavities depends very sensitively on the form of the assumed molecular interactions for dfferent classical simple point-charge models and quantum mechanical DFT-based interaction potentials, as reected in their description of donor and acceptor hydrogen bonds near the cavity. These dfferences can signifcantly affect the magnitude of the scalar electrostatic potential. We argue that the result of these studies will have direct consequences toward our understanding of the thermodynamics of ion solvation through the cavity charging process. JDW and RCR are supported by the National Science Foundation (Grants CHE0848574 and CHE1300993). CJM and GKS are supported by the U.S. Department of Energy`s (DOE) Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences. Pacific Northwest National Laboratory (PNNL) is operated for the Department of Energy by Battelle. MDB is grateful for the support of the Linus Pauling Distinguished Postdoctoral Fellowship Program at PNNL. We acknowledgemore » illuminating discussions and sharing of ideas and preprints with Dr. Shawn M. Kathmann and Prof. Tom Beck. The DFT simulations used resources of the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Additional computing resources were generously allocated by PNNL's Institutional Computing program.« less

Authors:
; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1170481
Report Number(s):
PNNL-SA-102866
KC0301020
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry Letters, 5(16):2767-2774
Country of Publication:
United States
Language:
English

Citation Formats

Remsing, Richard C., Baer, Marcel D., Schenter, Gregory K., Mundy, Christopher J., and Weeks, John D. The role of broken symmetry in solvation of a spherical cavity in classical and quantum water models. United States: N. p., 2014. Web. doi:10.1021/jz501067w.
Remsing, Richard C., Baer, Marcel D., Schenter, Gregory K., Mundy, Christopher J., & Weeks, John D. The role of broken symmetry in solvation of a spherical cavity in classical and quantum water models. United States. doi:10.1021/jz501067w.
Remsing, Richard C., Baer, Marcel D., Schenter, Gregory K., Mundy, Christopher J., and Weeks, John D. Thu . "The role of broken symmetry in solvation of a spherical cavity in classical and quantum water models". United States. doi:10.1021/jz501067w.
@article{osti_1170481,
title = {The role of broken symmetry in solvation of a spherical cavity in classical and quantum water models},
author = {Remsing, Richard C. and Baer, Marcel D. and Schenter, Gregory K. and Mundy, Christopher J. and Weeks, John D.},
abstractNote = {Insertion of a hard sphere cavity in liquid water breaks translational symmetry and generates an electrostatic potential difference between the region near the cavity and the bulk. Here, we clarify the physical interpretation of this potential and its calculation. We also show that the electrostatic potential in the center of small, medium, and large cavities depends very sensitively on the form of the assumed molecular interactions for dfferent classical simple point-charge models and quantum mechanical DFT-based interaction potentials, as reected in their description of donor and acceptor hydrogen bonds near the cavity. These dfferences can signifcantly affect the magnitude of the scalar electrostatic potential. We argue that the result of these studies will have direct consequences toward our understanding of the thermodynamics of ion solvation through the cavity charging process. JDW and RCR are supported by the National Science Foundation (Grants CHE0848574 and CHE1300993). CJM and GKS are supported by the U.S. Department of Energy`s (DOE) Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences. Pacific Northwest National Laboratory (PNNL) is operated for the Department of Energy by Battelle. MDB is grateful for the support of the Linus Pauling Distinguished Postdoctoral Fellowship Program at PNNL. We acknowledge illuminating discussions and sharing of ideas and preprints with Dr. Shawn M. Kathmann and Prof. Tom Beck. The DFT simulations used resources of the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Additional computing resources were generously allocated by PNNL's Institutional Computing program.},
doi = {10.1021/jz501067w},
journal = {Journal of Physical Chemistry Letters, 5(16):2767-2774},
number = ,
volume = ,
place = {United States},
year = {Thu Aug 21 00:00:00 EDT 2014},
month = {Thu Aug 21 00:00:00 EDT 2014}
}
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