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Title: Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry

Abstract

First-principles calculations combining density-functional theory and continuum solvation models enable realistic theoretical modeling and design of electrochemical systems. When a reaction proceeds in such systems, the number of electrons in the portion of the system treated quantum mechanically changes continuously, with a balancing charge appearing in the continuum electrolyte. A grand-canonical ensemble of electrons at a chemical potential set by the electrode potential is therefore the ideal description of such systems that directly mimics the experimental condition. We present two distinct algorithms: a self-consistent field method and a direct variational free energy minimization method using auxiliary Hamiltonians (GC-AuxH), to solve the Kohn-Sham equations of electronic density-functional theory directly in the grand canonical ensemble at fixed potential. Both methods substantially improve performance compared to a sequence of conventional fixed-number calculations targeting the desired potential, with the GC-AuxH method additionally exhibiting reliable and smooth exponential convergence of the grand free energy. Lastly, we apply grand-canonical density-functional theory to the under-potential deposition of copper on platinum from chloride-containing electrolytes and show that chloride desorption, not partial copper monolayer formation, is responsible for the second voltammetric peak.

Authors:
ORCiD logo [1]; ORCiD logo [2];  [3]
  1. Rensselaer Polytechnic Inst., Troy, NY (United States); California Inst. of Technology (CalTech), Pasadena, CA (United States)
  2. California Inst. of Technology (CalTech), Pasadena, CA (United States)
  3. Cornell Univ., Ithaca, NY (United States)
Publication Date:
Research Org.:
California Institute of Technology, Pasadena, CA (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE); USDOE Office of Science (SC)
OSTI Identifier:
1347429
Alternate Identifier(s):
OSTI ID: 1348036
Grant/Contract Number:
SC0004993; SC0001086; AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 146; Journal Issue: 11; Journal ID: ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 97 MATHEMATICS AND COMPUTING

Citation Formats

Sundararaman, Ravishankar, Goddard, III, William A., and Arias, Tomas A. Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry. United States: N. p., 2017. Web. doi:10.1063/1.4978411.
Sundararaman, Ravishankar, Goddard, III, William A., & Arias, Tomas A. Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry. United States. doi:10.1063/1.4978411.
Sundararaman, Ravishankar, Goddard, III, William A., and Arias, Tomas A. Thu . "Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry". United States. doi:10.1063/1.4978411. https://www.osti.gov/servlets/purl/1347429.
@article{osti_1347429,
title = {Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry},
author = {Sundararaman, Ravishankar and Goddard, III, William A. and Arias, Tomas A.},
abstractNote = {First-principles calculations combining density-functional theory and continuum solvation models enable realistic theoretical modeling and design of electrochemical systems. When a reaction proceeds in such systems, the number of electrons in the portion of the system treated quantum mechanically changes continuously, with a balancing charge appearing in the continuum electrolyte. A grand-canonical ensemble of electrons at a chemical potential set by the electrode potential is therefore the ideal description of such systems that directly mimics the experimental condition. We present two distinct algorithms: a self-consistent field method and a direct variational free energy minimization method using auxiliary Hamiltonians (GC-AuxH), to solve the Kohn-Sham equations of electronic density-functional theory directly in the grand canonical ensemble at fixed potential. Both methods substantially improve performance compared to a sequence of conventional fixed-number calculations targeting the desired potential, with the GC-AuxH method additionally exhibiting reliable and smooth exponential convergence of the grand free energy. Lastly, we apply grand-canonical density-functional theory to the under-potential deposition of copper on platinum from chloride-containing electrolytes and show that chloride desorption, not partial copper monolayer formation, is responsible for the second voltammetric peak.},
doi = {10.1063/1.4978411},
journal = {Journal of Chemical Physics},
number = 11,
volume = 146,
place = {United States},
year = {Thu Mar 16 00:00:00 EDT 2017},
month = {Thu Mar 16 00:00:00 EDT 2017}
}

Journal Article:
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Cited by: 5works
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  • Cited by 5
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