Targeted free energy perturbation revisited: Accurate free energies from mapped reference potentials
arXiv:2106.09295 · doi:10.1021/acs.jpclett.1c02135
Abstract
We present an approach that extends the theory of targeted free energy perturbation (TFEP) to calculate free energy differences and free energy surfaces at an accurate quantum mechanical level of theory from a cheaper reference potential. The convergence is accelerated by a mapping function that increases the overlap between the target and the reference distributions. Building on recent work, we show that this map can be learned with a normalizing flow neural network, without requiring simulations with the expensive target potential but only a small number of single-point calculations, and, crucially, avoiding the systematic error that was found previously. We validate the method by numerically evaluating the free energy difference in a system with a double-well potential and by describing the free energy landscape of a simple chemical reaction in the gas phase.
arXiv commentMain Text: 7 pages, 2 figures, 18 equations. Supplemental Material: 4 pages, 26 equations
References in corpus (18)
- Escaping free-energy minima
- A nonequilibrium equality for free energy differences
- PLUMED 2: New feathers for an old bird
- Well-Tempered Metadynamics: A Smoothly Converging and Tunable Free-Energy Method
- SchNet - a deep learning architecture for molecules and materials
- Statistically optimal analysis of samples from multiple equilibrium states
- Machine learning for molecular simulation
- Time-lagged autoencoders: Deep learning of slow collective variables for molecular kinetics
- Rethinking Metadynamics: from bias potentials to probability distributions
- MADE: Masked Autoencoder for Distribution Estimation
- Best Practices for Alchemical Free Energy Calculations
- Data-Driven Collective Variables for Enhanced Sampling
- Variational Encoding of Complex Dynamics
- Targeted free energy perturbation
- Accelerated Computation of Free Energy Profile at ab Initio Quantum Mechanical/Molecular Mechanics Accuracy via a Semi-Empirical Reference Potential. I. Weighted Thermodynamics Perturbation
- Targeted free energy estimation via learned mappings
- Using bijective maps to improve free energy estimates
- Reweighting from the mixture distribution as a better way to describe the Multistate Bennett Acceptance Ratio