2024-04-03 OpenFF/FE collab

• new solvation code path seems to work and produce sane reported results. need to run this for meaningful amount of time with either code path to check for estimate equality

• analytical System equality check

  • fuzziness allowed (all due to solvation):

    • sigma on hydrogens (these are 0)

    • system volume dimensions

    • number of waters

    • position of waters

  • should be strictly equal

    • barostat

    • thermostat

    • small molecule forces

    • FF applied to water

    • constraint distances

    • masses

• confidence in existing packmol implementation is high, this is tested elsewhere

• initial packmol configurations might be a bit sketchy

  • RG: Can adjust the initial equilibration parameters

• full scale validation on HPC is openff responsibility

Initial Validation requirements?

• for 5 ligands in water, statistically identical results with existing and new code paths

• pending getting SFE data

  • cherry pick 10 “well behaved” small molecules in non-aqueous solvent

  • acceptable agreement with experiment for 10 ligands in non-water solvent

• this should be computable in ~week

Future steps for solvation workflow

• will probably “release” skunkworks as a tag on github

  • MT to check if this is sufficient for initial openff requirements

• will eventually fold this work back into main openfe release line once we’re happy with final product

  • RG responsibility to finally merge this into main openfe repo

• after merge openff team can use mainline SFE openfe repo for this work