[gmx-users] PME vs. default electrostatics

[Arturas]

Hi all,

I did two full MD for the same drug-enzyme complex: one with PME and one
without any keyword of 'coulombtype' electrostatics
(rlist,rvdw,rcoulomb=1.0).

What coulombtype GROMACS uses by default if it is not specified in
*.mdp ?

My drug stays in complex with enzyme in both MD runs, but the
fluctuation character is very different: with PME it's more chaotic,
while without PME there is more ordered structure. Why these
differences exist ?

With best
Arturas