[gmx-users] difference of calculation time between the numbers of fep-lambdas values

[Hannes Loeffler]

On Mon, 27 Apr 2015 07:43:51 -0400
Justin Lemkul <jalemkul at vt.edu> wrote:

> Note that without couple-moltype, you're going to be decoupling the
> whole system, which is (1) not what you want for calculating
> solvation free energy and (2) extremely slow.  There is an inherent
> slowdown when running the free energy code, but it should not be so
> large.

Really? I just looked into the code yesterday and I think that if you do
not set couple-moltype, none of the coupling code is ever triggered.  I
have only played a bit with relative free energies (Gromacs 4.6) where I
think you don't need any of the couple- parameters at all.

Cheers,
Hannes.