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Title: Finding the Atomic Configuration with a Required Physical Property in Multi-Atom Structures

Abstract

In many problems in molecular and solid state structures one seeks to determine the energy-minimizing decoration of sites with different atom types. In other problems, one is interested in finding a decoration with a target physical property (e.g. alloy band gap) within a certain range. In both cases, the sheer size of the configurational space can be horrendous. We present two approaches which identify either the minimum-energy configuration or configurations with a target property for a fixed underlying Bravais lattice. We compare their efficiency at locating the deepest minimum energy configuration of face centered cubic Au-Pd alloy. We show that a global-search genetic-algorithm approach with diversity-enhancing constraints and reciprocal-space mating can efficiently find the global optimum, whereas the local-search virtual-atom approach presented here is more efficient at finding structures with a target property.

Authors:
;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
939509
DOE Contract Number:
AC36-99-GO10337
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physics: Condensed Matter; Journal Volume: 19; Journal Issue: 40, 2007
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ALLOYS; ATOMS; CONFIGURATION; EFFICIENCY; FCC LATTICES; MATING; TARGETS; Basic Sciences

Citation Formats

d'Avezac, M., and Zunger, A. Finding the Atomic Configuration with a Required Physical Property in Multi-Atom Structures. United States: N. p., 2007. Web. doi:10.1088/0953-8984/19/40/402201.
d'Avezac, M., & Zunger, A. Finding the Atomic Configuration with a Required Physical Property in Multi-Atom Structures. United States. doi:10.1088/0953-8984/19/40/402201.
d'Avezac, M., and Zunger, A. Mon . "Finding the Atomic Configuration with a Required Physical Property in Multi-Atom Structures". United States. doi:10.1088/0953-8984/19/40/402201.
@article{osti_939509,
title = {Finding the Atomic Configuration with a Required Physical Property in Multi-Atom Structures},
author = {d'Avezac, M. and Zunger, A.},
abstractNote = {In many problems in molecular and solid state structures one seeks to determine the energy-minimizing decoration of sites with different atom types. In other problems, one is interested in finding a decoration with a target physical property (e.g. alloy band gap) within a certain range. In both cases, the sheer size of the configurational space can be horrendous. We present two approaches which identify either the minimum-energy configuration or configurations with a target property for a fixed underlying Bravais lattice. We compare their efficiency at locating the deepest minimum energy configuration of face centered cubic Au-Pd alloy. We show that a global-search genetic-algorithm approach with diversity-enhancing constraints and reciprocal-space mating can efficiently find the global optimum, whereas the local-search virtual-atom approach presented here is more efficient at finding structures with a target property.},
doi = {10.1088/0953-8984/19/40/402201},
journal = {Journal of Physics: Condensed Matter},
number = 40, 2007,
volume = 19,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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