Hi,

I am stuck in a weird situation. We want to observe some bond breaking-formation in a QM/MM simulation and for the rest of the project, for MD simulations, I have used GROMACS 2018 with 54a7 forcefield.

I have defined the QM boundaries and linker parts successfully and want to run a QM/MM simulation with 6-31G basis set and DFT (correct me, if I'm heading towards wrong direction).

Now, I have doube-precision GROMACS installed already or I can recompile it from the source. But, it seems that GROMACS no more supports MOPAC library (they used to provide a *.a library file, as far as I can remember and then you had to recompile GROMACS with qmmm). My GROMACS installation is double precision and installed with -DGMX_MIMIC=ON (as far as I can remember i.e. with MIMIC).

The error messages I am getting say that GROMACS now only supports GAMESS and GAUSSIAN. However, Gaussian is unreasonably costly for a research lab located in India (under the present Government specifically). GAMESS-UK is not free for academics outside UK. However, GAMESS-US is free.

Does GROMACS 2018 support GAMESS-US? You can suggest me alternative ways too to do the same. I am open to suggestions.