Plan/build Yank workflow for running with SMIRNOFF forcefields

We want to be able to begin Yank calculations (especially, hydration free energy calculations) with SMIRNOFF forcefields (such as via the ForceField class which currently lives in https://github.com/open-forcefield-group/smarty; to be moved soon to a separate repo). What would be best is to get this implemented in Yank as an alternative to GAFF (or GAFF2) so that we can just switch small molecule force fields via a switch in the YAML.

Right now, it would be possible to use SMIRNOFF in Yank but it would have to be via the serialized XML route – e.g. I set up the system elsewhere, dump to XML, then read those in to Yank. While this can work, it makes it much more of a headache to get it into our Orion workflow, since it becomes a totally different workflow than the GAFF calculations, whereas if Yank is made SMIRNOFF-capable, then we could potentially switch between them via just a “force field” drop down menu.

@andrrizzi - @jchodera requested I post this and tag you. 😃

[davidlmobley]

OK, sounds good. Let me know what I can do to help you have the info you need as you get ready to work on it.

[jchodera]

I think this has been handled by https://github.com/MobleyLab/SMIRNOFF_paper_code for now. We’ll eventually support SMIRNOFF ForceField native pipelines once it works for biomolecules and small molecules.