Efficient and Accurate Car-Parrinello-like Approach to Born-Oppenheimer Molecular Dynamics

Abstract

We present a new method which combines Car-Parrinello and Born-Oppenheimer molecular dynamics in order to accelerate density functional theory based ab initio simulations. Depending on the system a gain in efficiency of 1 to 2 orders of magnitude has been observed, which allows ab initio molecular dynamics of much larger time and length scales than previously thought feasible. It will be demonstrated that the dynamics is correctly reproduced and that high accuracy can be maintained throughout for systems ranging from insulators to semiconductors and even to metals in condensed phases. This development considerably extends the scope of ab initio simulations.

Microscopic properties of liquid water from combined ab initio molecular dynamics and energy decomposition studies

“…The recently developed second-generation CPMD method combines the best of both approaches by retaining the large integration time steps of BOMD and, at the same time, preserving the efficiency of CPMD 14 . The propagation scheme in second-generation CPMD relies on the appropriate usage of the information about the electrons from the previous MD steps and, in contrast to CPMD, does not require a fictitious mass parameter to maintain the accuracy of the Born-Oppenheimer dynamics.…”

“…Presuming that the energy is exponentially decaying, which had been shown to be an excellent assumption 12,14,28 , it is possible to rigorously correct for the dissipation, by modelling the nuclear forces arising from our dynamics as:…”

“…In this section, we assess the magnitude of errors coming from physical approximations, finite-size effects and insufficient sampling by performing large-scale simulations, which exploit the computationally efficiency second-generation CPMD method 14,108 .…”

Inverse simulated annealing: Improvements and application to amorphous InSb

“…However, due to the large number of degrees of freedom of disordered systems, the annealing has to be conducted as slowly as possible and is therefore computationally exceedingly expensive. This is even more pronounced in conjunction with ab initio electronic structure calculations, in spite of recent progress 15,16 . As a consequence, the attainable quench-rates are typically several orders of magnitude faster than in experiment.…”

Stabilization ofAb InitioMolecular Dynamics Simulations at Large Time Steps

“…This algorithm may also be used in conjunction with other methods to accelerate the simulations even further, such as the Langevin dynamics [5][6][7][8] , linear scaling method [24][25][26] and mass scaling method 27 . …”