Gromos54a7 , Charmm FF

GROMACS version: 2018
GROMACS modification: No

Dear all,
I have performed a series of some long simulations for a large system containing some molecules for which the Gromos54a7 force fields have been used.
Now in the next step of my research project I want to study the behavior of the system gotten from the first step on top of the Silicon surface. Unfortunately I could not find any Gromos54a7 force fields for Silicon surface but Charmm FF is available for it.
Considering the fact that mixing systems with different force fields doesn’t make sense, what would you recommend to do so that I would not loose the results (resource) gotten (spent) from (for) the first step?

Thank you

If you don’t want to re-run the 54A7 simulations, then your only real option is to parametrize the silicon surface with the same force field. It’s up to you whether the time spent doing that (and whether or not you can get satisfactory results using that model) is worth it, or if re-running the simulations with CHARMM is more expedient.