Problem with calculating the interaction energy between two groups

GROMACS version: 2021.2
GROMACS modification: No

I’m following Justin’s tutorial on my system which is a solute and an organic solvent. I want to get the interaction energies between a shell layer of the solvent and the solute. I added these groups to my energygroup of the mdp file and rerun the simulation but I get 0 Coul-SR and vdW-SR for some reason.

If I define all solvents and solute as energygroup it’s all good and not going to be zero. But no matter how big is my shell, I always get 0. Does anybody know what’s wrong with my calculations?


This usually happens when the calculations are done on a GPU, which cannot handle energy groups. Make sure to add -nb cpu to your mdrun command line if you are running the calculations on a machine with a compatible GPU to prevent it from being used.

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