# Force-field functor theory: classical force-fields which reproduce equilibrium quantum distributions

@article{Babbush2013ForcefieldFT, title={Force-field functor theory: classical force-fields which reproduce equilibrium quantum distributions}, author={Ryan Babbush and John A. Parkhill and Al{\'a}n Aspuru-Guzik}, journal={Frontiers in Chemistry}, year={2013}, volume={1} }

Feynman and Hibbs were the first to variationally determine an effective potential whose associated classical canonical ensemble approximates the exact quantum partition function. We examine the existence of a map between the local potential and an effective classical potential which matches the exact quantum equilibrium density and partition function. The usefulness of such a mapping rests in its ability to readily improve Born-Oppenheimer potentials for use with classical sampling. We show…

## 6 Citations

### Response to Commentary on “Force-field functor theory: classical force-fields which reproduce equilibrium quantum distributions”

- MathematicsFront. Chem.
- 2013

The manuscript describes a new perspective on how the effective potential might be obtained in a spirit similar to Density Functional Theory (DFT) and demonstrates its impressive performance on independent test problems including the simulation of liquid hydrogen at temperatures as low as 14 K.

### Response to Commentary on “Force-field functor theory: classical force-fields which reproduce equilibrium quantum distributions”

- PhysicsFrontiers in chemistry
- 2013

### Reproducing Quantum Probability Distributions at the Speed of Classical Dynamics: A New Approach for Developing Force-Field Functors.

- PhysicsThe journal of physical chemistry letters
- 2018

This work proposes an efficient method of computing FFF using the Wigner-Kirkwood expansion, and calculates a range of thermodynamic properties of Neon, obtaining the same level of accuracy as RPMD, but with the shorter runtime of classical simulations.

### Rigorous force field optimization principles based on statistical distance minimization.

- Computer ScienceThe Journal of chemical physics
- 2015

We use the concept of statistical distance to define a measure of distinguishability between a pair of statistical mechanical systems, i.e., a model and its target, and show that its minimization…

### Towards Viable Quantum Computation for Chemistry

- Computer Science
- 2015

A protocol for preparing configuration interaction states that is asymptotically superior to all prior results and the details of the most accurate experimental quantum simulation of chemistry ever performed are included.

### Commentary on “Force-field functor theory: classical force-fields which reproduce equilibrium quantum distributions”

- PhysicsFront. Chem.
- 2013

This comment regards a recently published preprint by R.Babbush, J.A.Parkhill, and A.Aspuru-Guzik, arXiv:1306.4332.

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