[gmx-users] Solvation Free Energy using PME

[Ilya Chorny]

I would like to calc the solvation free energy of a negative ion in water
using perturbation.
Is it possible using PME. If I include a counter ion it will contribute to
the solvation free energy?
Could I use a reaction field instead of PME(how different will my results
be?). I tried the switching
function for my long range forces but I have been experiencing instability
using the switching
function. Any recomendations would be greatly apprecited.

Thanks

Ilya