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arXiv · 1908.08510

Speeding-up Ab Initio Molecular Dynamics with Hybrid Functionals using Adaptively Compressed Exchange Operator based Multiple Timestepping

Sagarmoy Mandal·Nisanth N. Nair
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Abstract

Ab initio molecular dynamics (AIMD) simulations using hybrid density functionals and plane waves are of great interest owing to the accuracy of this approach in treating condensed matter systems. On the other hand, such AIMD calculations are not routinely carried out since the computational cost involved in applying the Hartree Fock exchange operator is very high. In this work, we make use of a strategy that combines adaptively compressed exchange operator formulation and multiple time step integration to significantly reduce the computational cost of these simulations. We demonstrate the efficiency of this approach for a realistic condensed matter system.

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Sagarmoy Mandal, Nisanth N. Nair. 2019-08-22. Speeding-up Ab Initio Molecular Dynamics with Hybrid Functionals using Adaptively Compressed Exchange Operator based Multiple Timestepping. https://doi.org/10.1063/1.5125422

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