[gmx-users] SEP and HO atom type - again

[Anton Feenstra]

Luciane Vieira de Mello wrote:
> Dear all,
> 
> another weird thing I found was the difference between
> ffgmx2nb.itp and ffG43b1nb.itp files.
> The first one has a mass for all the atoms type, while in the second all
> the masses are set to zero.
[...]

Yes: for the Gromos forcefield (ffG43*) the masses of atoms are defined
in the .rtp entries, or in the molecule topologies themselves. For the
Gromacs forcefields (ffgmx*), they are defined for the atom types.
Still, Gromacs expects a mass field in the atom type definition, so they
are set to 0 (for the ffG43*nb.itp)


-- 
Groetjes,

Anton
  ________ ___________________________________________________________
|        | Anton Feenstra                                            |
| .      | Dept. of Pharmacochemistry - Vrije Universiteit Amsterdam |
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