GROMACS version:2023.2
GROMACS modification: Yes/No
When I followed this tutorial PLUMED: Using Hamiltonian replica exchange with GROMACS and “heated” my solute RNA molecule, since the electrostatic parameters were also scaled, when executing grompp, a warning about uneven charges would be raised. After the electrostatic parameters are scaled, this charge usually deviates significantly from 0. At this point, is it necessary to reprocess this charge?
As the tutorial points out later
Notice that total cell could be charged. This happens whenever the scaled portion of the system is not neutral. There should be no problem in this. When used with pbc, GROMACS will add a compensating background.
So no. When you compile the new .tpr, just -maxwarn 1 the charged box to conclude the grompp preprocessing. You can also see it reported in between the various commands of the tutorial, e.g. this one
# -maxwarn is often needed because box could be charged
grompp_mpi_d -maxwarn 1 -o topol$i.tpr -f grompp$i.mdp -p topol$i.top