Improved Ab Initio Molecular Dynamics by Minimal Biasing with Experimental Data

Abstract

Accounting for electrons and nuclei simultaneously is a powerful capability of ab initio molecular dynamics (AIMD). However, AIMD is often unable to accurately reproduce properties of systems such as water due to inaccuracies in the underlying electronic density functionals. This shortcoming is often addressed by added empirical corrections and/or increasing the simulation temperature. We present here a maximum-entropy approach to directly incorporate limited experimental data via a minimal bias. Biased AIMD simulations of water and an excess proton in water are shown to give significantly improved properties both for observables which were biased to match experimental data and for unbiased observables. This approach also yields new physical insight into inaccuracies in the underlying density functional theory as utilized in the unbiased AIMD.

30 pages, 9 figures, 1 table

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Cited by in corpus (5)

• Using the Maximum Entropy Principle to Combine Simulations and Solution Experiments
• The Hopping Mechanism of the Hydrated Excess Proton and Its Contribution to Proton Diffusion in Water
• Recent Advances in Maximum Entropy Biasing Techniques for Molecular Dynamics
• An implementation of the maximum-caliber principle by replica-averaged time-resolved restrained simulations
• Combining Enhanced Sampling with Experiment Directed Simulation of the GYG peptide