Using GROMOS Force Field in lammps

Hi,

I want to use GROMOS Force Field in lammps. I noticed that I can use some_styles in lammps source field as the energy functions for angle and dihedral. And I can also use lj/gromacs for non-bonded interactions. However I cannot find that for bond calculation while for GROMOS it should be k(b^2 - b0^2)^2. I think it should be similar with the harmonic bond style and I want to adapt the cpp file for harmonic bond style in src folder so that I can use that to calculate bond interaction in GROMOS force field. What variables in the cpp file should I change? Just the variable for energy like energy = k(b - b0)^2 to energy = k(b^2 - b0^2)^2? Or do I need to change the variables for others like force?

Thanks,

Faust

Hi,

I want to use GROMOS Force Field in lammps. I noticed that I can use
some_styles in lammps source field as the energy functions for angle and
dihedral. And I can also use lj/gromacs for non-bonded interactions. However
I cannot find that for bond calculation while for GROMOS it should be k(b^2
- b0^2)^2. I think it should be similar with the harmonic bond style and I
want to adapt the cpp file for harmonic bond style in src folder so that I
can use that to calculate bond interaction in GROMOS force field. What
variables in the cpp file should I change? Just the variable for energy like
energy = k(b - b0)^2 to energy = k(b^2 - b0^2)^2? Or do I need to change the
variables for others like force?

you need to include forces as well. since this is straightforward to
implement, i've just created this bond style and submitted it for
inclusion into the next LAMMPS patch release.
you can find the pull request here: https://github.com/lammps/lammps/pull/694

axel.