open force field

An open and collaborative approach to better force fields

Science Updates

Announcing two new releases!

Posted on 27 Oct 2020 by David Mobley, Karmen Condic-Jurkic

We’re pleased to announce TWO releases are now available!

Force fields

OpenFF-1.3.0, a minor update to Parsley that improves performance on amide geometries. Detailed release notes are available here.

OpenFF Toolkit

The Open Force Field Toolkit version 0.8.0. This release adds our largest feature yet, SMARTS-based creation of VirtualSites (also known as off-center charges), as well as functionality to handle bond parameter interpolation based on partial bond orders. Detailed release notes are available at here.

The latest version of the toolkit can be installed into a new environment using conda, with conda create -n openforcefield -c conda-forge -c omnia openforcefield. conda packages for both are available now on the omnia channel:

Single-file installers are available in the “assets” section of the GitHub release.

To provide feedback on performance of the OpenFF force fields, we highly recommend using the issue tracker at For toolkit feedback, use Alternatively, inquiries may be e-mailed to, though responses to e-mails sent to this address may be delayed and GitHub issues receive higher priority.