[gmx-users] GB parameter(s) missing or negative for atom type 'xxx'.

[Dd H]

Hi,
I want to simulate a protein-ligand complex with implicit solvent. After I
ran "grompp" command it prompted me there were some missing GB parameters.
I guess the problem is that some atom types in my system are not included
in the gbsa.itp file.
If it is the case, do you know where can I find the missing GB parameters?
Especially the Mg and P elements.

Thank you in advance!
Dading Huang