2025-09-16 FF Fitting Meeting

MNSol benchmarks with rc2 fits

• DM: Is there another tested property other than salvation free energies of MNSol that we could have used to predict this?

  • LW: I don’t think so

  • DM: It looks like we have an unlucky chemical mixture set in MNSol

  • LW: It does seem that there is a systematic issue with aromatics

  • DM: Could it be aromatics with nitrogens?

  • LW: It’s possible, but not in all cases

• BS: For the N compounds that look fishy, how is Hvap and Hmix? Also it seems there is a Br issue.

  • LW: I haven’t looked at Hvap, but Hmix looks fine

  • BS: It’s interesting that the trends are so consistent where the new FF predicted Gsolv lower than the old FF

Dipole difference in MNSol Molecules

• DM: Is this specific to MNSol molecules or is this also true of our training dataset?

  • LW: I’m not sure off the top of my head, I’ll have to report that later

• CC: Is the exp dipole gas or liquid phase?

  • LW: Oh now that you ask it might be gas, I’ll need to confirm

• DM: I think the RBFEs should drive the decision on what FF version should be 2.3

• BS: How many ???

  • LW: 8

  • BS: Oh good