VMD-L Mailing List

From: Aleksei (erdelgado_at_udec.cl)
Date: Fri Mar 26 2021 - 14:19:52 CDT

Hi,

CGenFF is not designed specifically to use MP2, to optimize the geometry
(and scan the dihedrals) you may use the highest level of theory
practical for your molecule. The only part where you are forced to use a
particular method is when parametrizing the charges.

El 26/3/21 a las 13:15, Smith, Harper E. escribió:

> Hi mailing list,
>
> It seems like FFTK is designed specifically for use at the MP2 level
of theory. Unfortunately, my small molecule is optimized to the wrong
geometry at MP2, but something much closer at HF (especially if I add
implicit water).
>
> It seems like my options are:
>
>   *   Stick to the protocol by proceeding with the flawed geometry
that comes from an MP2 optimization
>   *   Deviate from the protocol by switching to HF/SMD, but use a
clearly better geometry
>
> Does anyone have any experience with this? Which of these options
should I prefer? It seems like either option will give non-ideal
results, but I lack the experience to judge which is better.
>
> Best,
> Harper Smith