# Is pressure equilibration not necessory with charmm-gui in gromacs simulation? **URL:** \ **Category:** User discussions\ **Created:** [June 10, 2020, 2:16pm UTC](https://gromacs.bioexcel.eu/t/is-pressure-equilibration-not-necessory-with-charmm-gui-in-gromacs-simulation/284 "2020-06-10T14:16:10Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Azam](https://avatars.discourse-cdn.com/v4/letter/a/ea666f/32.png) [@Azam](https://gromacs.bioexcel.eu/u/Azam)\ **Post date:** [June 10, 2020, 2:16pm UTC](https://gromacs.bioexcel.eu/t/is-pressure-equilibration-not-necessory-with-charmm-gui-in-gromacs-simulation/284/1 "2020-06-10T14:16:10Z")
GROMACS version:2019 Hello all. i tried to use charmm-gui in order to generate input files for simulation of my enzyme in water with gromacs . I have a gromacs subdirectory containing a gromacs inputs and a shell script template (in README) for running the inputs. there are three mdp files: step4.0\_minimization.mdp, step4.0\_minimization.mdp and step5\_production.mdp. but according to gromacs tutorials. we need nvt.mdp and npt.mdp. Is step4.0\_minimization.mdp for temprature equilibration? and we dont need pressure equilibration with charmm-gui? ---
**Author:** ![jalemkul](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/jalemkul/32/18_2.png) [@jalemkul](https://gromacs.bioexcel.eu/u/jalemkul)\ **Post date:** [June 10, 2020, 3:48pm UTC](https://gromacs.bioexcel.eu/t/is-pressure-equilibration-not-necessory-with-charmm-gui-in-gromacs-simulation/284/2 "2020-06-10T15:48:08Z")
> [@Azam](#): > > there are three mdp files: step4.0\_minimization.mdp, step4.0\_minimization.mdp and step5\_production.mdp Presumably you’ve got a typo here and there is a step4.1\_equilibration.mdp or something similar. > [@Azam](#): > > according to gromacs tutorials. we need nvt.mdp and npt.mdp. There is no “one size fits all” for equilibrating simulation systems. The tutorial I wrote presents one possible method. It is not the only one.