[lammps-users] pressure value not matching with fix NPT.

I am trying to do NPT simulation of tip4p water. Fixing the temperature at 400K and pressure at 1atm, When calculating the pressure during the simulation, it’s coming higher than the fixed value.
I am attaching my input file and the pressure data file.

Need some help.

Thanks and regards,

pressdata.log (20.2 KB)

tip4p_water,in (1.11 KB)

How big is your system? What is happening to the box size if the pressure
remains above 1.0 for a long time?