[gmx-users] Net charge error

[Siddhesh Kamat]

Hello everyone,
 I am working on a monoprotic Napthenic acid(a simple straight chain one
C29H59COOH). I made the .itp file and used PRODRG for the .gro file. I am
unable to energy minimise the system after adding TIP4P water. The error I
am getting is 'net charge is non zero and the number it gives is about
453(it gives a decimal actually). I have thoroughly checked the .itp and
.top files. The number that GROMACS gives is actually very close to the
total mass of the system. I am using GROMACS version 5.04 and I am
relatively pretty new to GROMACS. Please suggest what may be the possible
problem.