GROMACS Stochastic Dynamics and BAOAB are equivalent configurational sampling algorithms

Stefanie Kieninger; Bettina G. Keller

doi:10.1021/acs.jctc.2c00585

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arXiv · 2204.02105

GROMACS Stochastic Dynamics and BAOAB are equivalent configurational sampling algorithms

Stefanie Kieninger·Bettina G. Keller

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Abstract

Two of the most widely used Langevin integrators for molecular dynamics simulations are the GROMACS Stochastic Dynamics (GSD) integrator and the splitting method BAOAB. In this letter, we show that the GROMACS Stochastic Dynamics integrator is equal to the less frequently used splitting method BAOA. It immediately follows that GSD and BAOAB sample the same configurations and have the same high configurational accuracy. Our numerical results indicate that GSD/BAOA has higher kinetic accuracy than BAOAB.

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Stefanie Kieninger, Bettina G. Keller. 2022-04-05. GROMACS Stochastic Dynamics and BAOAB are equivalent configurational sampling algorithms. https://doi.org/10.1021/acs.jctc.2c00585

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