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arXiv · 2102.00289

Nuclear Quantum Effects in liquid water at near classical computational cost using the adaptive Quantum Thermal Bath

Nastasia Mauger·Thomas Plé·Louis Lagardère·Sara Bonella·Etienne Mangaud·Jean-Philip Piquemal·Simon Huppert
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Abstract

We demonstrate the accuracy and efficiency of a recently introduced approach to account for nuclear quantum effects (NQE) in molecular simulations: the adaptive Quantum Thermal Bath (adQTB). In this method, zero point energy is introduced through a generalized Langevin thermostat designed to precisely enforce the quantum fluctuation-dissipation theorem. We propose a refined adQTB algorithm with improved accuracy and we report adQTB simulations of liquid water. Through extensive comparison with reference path integral calculations, we demonstrate that it provides excellent accuracy for a broad range of structural and thermodynamic observables as well as infrared vibrational spectra. The adQTB has a computational cost comparable to classical molecular dynamics, enabling simulations of up to millions of degrees of freedom.

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Nastasia Mauger, Thomas Plé, Louis Lagardère, Sara Bonella, Etienne Mangaud, Jean-Philip Piquemal, Simon Huppert. 2021-01-30. Nuclear Quantum Effects in liquid water at near classical computational cost using the adaptive Quantum Thermal Bath. https://doi.org/10.1021/acs.jpclett.1c01722

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