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Title: Absorbing boundary conditions for molecular dynamics and multiscale modeling

Abstract

We present an application of differential equation based local absorbing boundary conditions to molecular dynamics. The absorbing boundary conditions result in the absorption of the majority of waves incident perpendicular to the bounding surface. We demonstrate that boundary conditions developed for the wave equation can be applied to molecular dynamics. Comparisons with damping material boundary conditions are discussed. The concept is extended to the formulation of an atomistic-continuum multiscale scheme with handshaking between the regions based on absorbing boundary conditions. The multiscale model is effective in minimizing spurious reflections at the interface.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Center for Computational Sciences
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC)
OSTI Identifier:
932028
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 76; Journal Issue: 8
Country of Publication:
United States
Language:
English
Subject:
97; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; ABSORPTION; BOUNDARY CONDITIONS; DAMPING; DIFFERENTIAL EQUATIONS; MOLECULAR DYNAMICS METHOD; WAVE EQUATIONS

Citation Formats

Namilae, Sirish, Nicholson, Don M, Nukala, Phani K, Gao, Carrie Y, Osetskiy, Yury N, and Keffer, David J. Absorbing boundary conditions for molecular dynamics and multiscale modeling. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.76.144111.
Namilae, Sirish, Nicholson, Don M, Nukala, Phani K, Gao, Carrie Y, Osetskiy, Yury N, & Keffer, David J. Absorbing boundary conditions for molecular dynamics and multiscale modeling. United States. doi:10.1103/PhysRevB.76.144111.
Namilae, Sirish, Nicholson, Don M, Nukala, Phani K, Gao, Carrie Y, Osetskiy, Yury N, and Keffer, David J. Mon . "Absorbing boundary conditions for molecular dynamics and multiscale modeling". United States. doi:10.1103/PhysRevB.76.144111.
@article{osti_932028,
title = {Absorbing boundary conditions for molecular dynamics and multiscale modeling},
author = {Namilae, Sirish and Nicholson, Don M and Nukala, Phani K and Gao, Carrie Y and Osetskiy, Yury N and Keffer, David J},
abstractNote = {We present an application of differential equation based local absorbing boundary conditions to molecular dynamics. The absorbing boundary conditions result in the absorption of the majority of waves incident perpendicular to the bounding surface. We demonstrate that boundary conditions developed for the wave equation can be applied to molecular dynamics. Comparisons with damping material boundary conditions are discussed. The concept is extended to the formulation of an atomistic-continuum multiscale scheme with handshaking between the regions based on absorbing boundary conditions. The multiscale model is effective in minimizing spurious reflections at the interface.},
doi = {10.1103/PhysRevB.76.144111},
journal = {Physical Review B},
number = 8,
volume = 76,
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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