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Small Molecule Template Generator for CHARMM36 (CgenFF)

Open dohyeonscottkim opened this issue 8 months ago • 1 comments

Hi, thank you for updating the CHARMM36 force field to July 2024 release!

I'm trying to use it, but it seems there's currently no small molecule template generator (like GAFFTemplateGenerator) available for CHARMM36. Is there a recommended way to include small molecules - such as those parameterized by CGenFF - when using the CHARMM36 protein and water models?

Thanks again for your great work!

dohyeonscottkim avatar Apr 22 '25 03:04 dohyeonscottkim

Currently we don't plan to support this directly since unfortunately CGenFF (the parameterization program) is not freely available to install: see #317. However, if you have access to CGenFF to parameterize your small molecule, and can parameterize the rest of your system using CHARMM or some other tool like CHARMM-GUI, etc., you should be able to use OpenMM's CharmmPsfFile and CharmmParameterSet to load in the CHARMM RTF/PRM/STR/PSF files.

epretti avatar Apr 22 '25 15:04 epretti