[gmx-users] Invalid order for directive bondtypes

[Elham Gholamrezai]

Dear all

I am working on simulation of hydrogen adsorption on graphene sheet, and I need to adopte my force field parameters, new force field folder is made and put in top directory of gromacs. For this reason, I modified "charmm27.ff" and included new files (bond.itp, nonbond.itp, n2t, atp, rtp, force field.itp) in it first, then topology file was produced by g_x2top command without any error. But when I grompp for minimization, I got the following error. How can I solve it? I used this command for grompp 

grompp -f em.mdp -c conf.gro -p topol.top -o em.tpr -n index.ndx

(also conf.gro include hydrogen and graphene sheet)
 

Fatal error:
Syntax error - File ffbonded.itp, line 1
Last line read:
'[ bondtypes ]'
Invalid order for directive bondtypes

I also attach ffbonded.itp file.

 any help is appreciated.