2025-11-25 FF Fitting Meeting

2025-11-25 FF Fitting Meeting

 

Participants

  • Bill Swope

  • @Jennifer Clark

  • @David Mobley

  • @Michael Shirts

  • @Pavan Behara

  • @Lily Wang

  • Adam Hogan

 

Share link: https://us06web.zoom.us/rec/share/MU47fb_MWANZr3KHoQ69CJBYyu3JNjn7O5MbqVSARkIXgQqpgYBmOY70jwH9RcsL.UjMUb-PBEcpnGz0p

Passcode: Tiq.@3.u

Discussion topics

Notes

Notes

  • JC: did you need to reduce timestep at all from 2 fs for the steeper repulsion in the condensed phase benchmarks?

    • AH: not really. Molecules spend most of their time in the bottom of the potential well. I used 2 fs. r^14 is incredibly steep, there winds up being a singularity that you don’t get with the exponential. Possibly if you did GCMC where you could overlap 2 atoms, you would need to reject superposition immediately or you might get fusion. I had to make a change to Evaluator to fix error handling, but otherwise these are all the base settings.

  • LW: you mentioned that you implemented polarisation in smee, have you done fits with it?

    • AH: the smee work was earlier this year. Descent gave me lots of warnings in the documentation that it’s experimental, so I never ran any fits with it. I did a proof of concept directly using smee, not with descent. Right now I have a big software dependency loop. I can’t use smee with the AmoebaMultipoleForce, so I have to write my own force.

  • JC: back to RMSDs with density – difference between green and blue bars?

    • AH: blue is the properties in the Sage 2.0 training dataset, green (TPL) are another NIST dataset.

 

 

 

 

 

 

Action items

Decisions