VS1 Approach II: re-fitting with some debugging

 

Re-fitting to complete set of data and with some debugging

Overview

Summary

In Approach I it was discovered that the wildly varying pyridine virtual site charge likely came from a couple bugs and from fitting to incomplete data. Re-fitting to the complete set of data, with fixed code, drastically improved the pyridine virtual site, as well as pyridine condensed phase properties. However, the new charge of 0.17 e was now considered potentially too low when presented, and the decision was made to try restraining to initial values in Approach III.

GitHub repo/branch

 

Status

Won't progress

 Milestones and metrics

 

Stage

Milestone/Benchmark

Contributors

Deadline

Status

Stage

Milestone/Benchmark

Contributors

Deadline

Status

Train virtual sites and BCCs to existing HF/6-31G* data

Re-fit 2.1.0 BCCs and virtual sites to ESP data, with bugs fixed

@Lily Wang

Oct 2023

Completed

Re-fit valence and vdW parameters to condensed phase properties

Re-fit FF terms for vsites-candidate, existing vdW sites

@Lily Wang

Nov 2023

Completed

 

Re-fit FF terms for vsites-candidate, with N split into two following findings in Approach I

@Lily Wang

Nov 2023

Completed

Benchmark

Improved or equivalent performance for molecules with virtual sites added (Cl, Br, pyridines) on training data

@Lily Wang

Nov 2023

Failed

Progress and findings

Re-fitting to full data

The greatest impact this had was on the pyridine virtual site, which changed from a charge magnitude of 1+e to 0.17e.

 

Re-fitting to condensed-phase properties

This significantly improved condensed phase properties for pyridine (presentation: https://docs.google.com/presentation/d/1HNK260eEh7dMPGbvQfPHWQ8VPIigvy5tgEXio2bSm-M/edit#slide=id.g25ce1cb38dd_1_26 ), although not more so than simply retraining BCCs. However, it was suggested that the 0.17e virtual site is now lower than expected, so the decision was made to investigate the effect of restraining to the initial guess in Approach III.

Screenshot 2024-10-11 at 1.48.02 pm.png