Journal
JOURNAL OF CHEMICAL PHYSICS
Volume 154, Issue 5, Pages -Publisher
AIP Publishing
DOI: 10.1063/5.0038190
Keywords
-
Funding
- U.S. Department of Energy Office of Basic Energy Sciences (FWP LANLE8AN)
- U.S. Department of Energy through the Los Alamos National Laboratory
- U.S. Department of Energy [892333218NCA000001]
Ask authors/readers for more resources
The extended Lagrangian Born-Oppenheimer molecular dynamics (XL-BOMD) is formulated for orbital-free Hohenberg-Kohn density functional theory and charge equilibration and polarizable force-field models. It introduces features such as a metric tensor generalization, preconditioners, and the use of a single Coulomb summation for determining fully equilibrated charges and interatomic forces. The orbital-free formulation allows for separate treatment of short-range energy terms and long-range electrostatic interactions, demonstrating accuracy, convergence, and stability in molecular dynamics simulations.
Extended Lagrangian Born-Oppenheimer molecular dynamics (XL-BOMD) [A. M. N. Niklasson, Phys. Rev. Lett. 100, 123004 (2008)] is formulated for orbital-free Hohenberg-Kohn density-functional theory and for charge equilibration and polarizable force-field models that can be derived from the same orbital-free framework. The purpose is to introduce the most recent features of orbital-based XL-BOMD to molecular dynamics simulations based on charge equilibration and polarizable force-field models. These features include a metric tensor generalization of the extended harmonic potential, preconditioners, and the ability to use only a single Coulomb summation to determine the fully equilibrated charges and the interatomic forces in each time step for the shadow Born-Oppenheimer potential energy surface. The orbital-free formulation has a charge-dependent, short-range energy term that is separate from long-range Coulomb interactions. This enables local parameterizations of the short-range energy term, while the long-range electrostatic interactions can be treated separately. The theory is illustrated for molecular dynamics simulations of an atomistic system described by a charge equilibration model with periodic boundary conditions. The system of linear equations that determines the equilibrated charges and the forces is diagonal, and only a single Ewald summation is needed in each time step. The simulations exhibit the same features in accuracy, convergence, and stability as are expected from orbital-based XL-BOMD.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available