2021-01-19 Meeting notes

Current status

AM1BCC and VdW Refit Results

@Simon Boothroyd

Proposed next steps

Several possible directions:

• Start optimisation / solve least squares problem direct. Are we stuck in a local minima?

  Don't necessarily need to benchmark produced charges, but would be good to see how different they are.
  
  

• Ethers seem to be the most problematic. Need to analyse this further.

  • Perform analysis of the gradients during fitting - are ethers trying to constrain the parameters differently than the rest of the data?

  • Split the analysis into polar and non-polar. Electric field expected to yield better results for polar molecules over non-polar. Need to determine if the test set is balanced too much towards non-polar.

  • Potentially look more into fitting to ESP rather than electric field?

• Maybe we need to expand the sets to include some nitrogen data to see the real benefits of the refits?

@Simon Boothroyd

• OM - Adding N data would be large expansion of the scope. Need to rethink data set, number of BCCs involving N very large. Benefit of looking at smaller set is allows to tease out more easily the subtle effects going on.