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Title: First principles molecular dynamics without self-consistent field optimization

Abstract

We present a first principles molecular dynamics approach that is based on time-reversible extended Lagrangian Born-Oppenheimer molecular dynamics [A. M. N. Niklasson, Phys. Rev. Lett. 100, 123004 (2008)] in the limit of vanishing self-consistent field optimization. The optimization-free dynamics keeps the computational cost to a minimum and typically provides molecular trajectories that closely follow the exact Born-Oppenheimer potential energy surface. Only one single diagonalization and Hamiltonian (or Fockian) construction are required in each integration time step. The proposed dynamics is derived for a general free-energy potential surface valid at finite electronic temperatures within hybrid density functional theory. Even in the event of irregular functional behavior that may cause a dynamical instability, the optimization-free limit represents a natural starting guess for force calculations that may require a more elaborate iterative electronic ground state optimization. Our optimization-free dynamics thus represents a flexible theoretical framework for a broad and general class of ab initio molecular dynamics simulations.

Authors:
 [1];  [2]
  1. Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Box 516, SE-75120 Uppsala (Sweden)
  2. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Publication Date:
OSTI Identifier:
22255189
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 140; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BORN-OPPENHEIMER APPROXIMATION; DENSITY FUNCTIONAL METHOD; FREE ENERGY; GROUND STATES; HAMILTONIANS; LAGRANGIAN FUNCTION; MOLECULAR DYNAMICS METHOD; OPTIMIZATION; POTENTIAL ENERGY; SELF-CONSISTENT FIELD; SIMULATION; SURFACES

Citation Formats

Souvatzis, Petros, E-mail: petros.souvatsiz@fysik.uu.se, and Niklasson, Anders M. N., E-mail: amn@lanl.gov. First principles molecular dynamics without self-consistent field optimization. United States: N. p., 2014. Web. doi:10.1063/1.4862907.
Souvatzis, Petros, E-mail: petros.souvatsiz@fysik.uu.se, & Niklasson, Anders M. N., E-mail: amn@lanl.gov. First principles molecular dynamics without self-consistent field optimization. United States. doi:10.1063/1.4862907.
Souvatzis, Petros, E-mail: petros.souvatsiz@fysik.uu.se, and Niklasson, Anders M. N., E-mail: amn@lanl.gov. Tue . "First principles molecular dynamics without self-consistent field optimization". United States. doi:10.1063/1.4862907.
@article{osti_22255189,
title = {First principles molecular dynamics without self-consistent field optimization},
author = {Souvatzis, Petros, E-mail: petros.souvatsiz@fysik.uu.se and Niklasson, Anders M. N., E-mail: amn@lanl.gov},
abstractNote = {We present a first principles molecular dynamics approach that is based on time-reversible extended Lagrangian Born-Oppenheimer molecular dynamics [A. M. N. Niklasson, Phys. Rev. Lett. 100, 123004 (2008)] in the limit of vanishing self-consistent field optimization. The optimization-free dynamics keeps the computational cost to a minimum and typically provides molecular trajectories that closely follow the exact Born-Oppenheimer potential energy surface. Only one single diagonalization and Hamiltonian (or Fockian) construction are required in each integration time step. The proposed dynamics is derived for a general free-energy potential surface valid at finite electronic temperatures within hybrid density functional theory. Even in the event of irregular functional behavior that may cause a dynamical instability, the optimization-free limit represents a natural starting guess for force calculations that may require a more elaborate iterative electronic ground state optimization. Our optimization-free dynamics thus represents a flexible theoretical framework for a broad and general class of ab initio molecular dynamics simulations.},
doi = {10.1063/1.4862907},
journal = {Journal of Chemical Physics},
number = 4,
volume = 140,
place = {United States},
year = {Tue Jan 28 00:00:00 EST 2014},
month = {Tue Jan 28 00:00:00 EST 2014}
}
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