Dear Amber Mailing List,
I am using the AMBER program for QM/MM of Peptides and Proteins, and recently came across the machine learning corrected PM6 model as discussed in this paper:
https://pubs.acs.org/doi/10.1021/acs.jctc.4c01330
I have tested it for amino-acids in the gas-phase and it appears to provide extremely accurate structures. For this reason I tried to run the approach in AMBER with MOPAC as an external program used via ORCA.
(AMBER as the QM/MM driver, ORCA as the external QM program, and in ORCA I used external tools:
https://github.com/faccts/orca-external-tools/
which allowed to link AMBER to the PM6ML-MOPAC version provided here:
https://github.com/Honza-R/mopac-ml
)
Unfortunately, the computations break down, as no point-charge gradient are provided.
Is there maybe a different way to use such models?
Can anyone tell me if the reason is that point charges are not supported (yet) by such models?
(for gXTB tested via the same approach I get the same result)
On the other hand, it there any plans for the future to include such models into the program?
Any hints or suggestions would be highly appreciated.
Thank you very much, and best regards,
Caspar
_______________________________________________
AMBER mailing list
AMBER.ambermd.org
http://lists.ambermd.org/mailman/listinfo/amber
Received on Wed Mar 25 2026 - 01:30:02 PDT
