I want to create data file and input file for Graphene.
first, I make .pdb and .psf files for graphene in VMD.
then I use charmm2lammps.pl script and par_all27_prot_lipid.prm and its topology file to make data file for lammps.
But in this step, every thing is OK except the improper coefficients and there is no improper coeff. for graphene in this parameter file.
Please help me to create this data file, if possible.