Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

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1

GROMACS version: 2019.3
GROMACS modification: ?

I’m trying to set up a new Force Field, and when I try using Restricted or CBT Dihedrals and running grompp I keep getting this really strange error (shown below for CBT, but get a similar output when using Restricted).

Is there any way to fix this please?

"ERROR 1 [file ffbonded.itp, line 73]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 2 [file ffbonded.itp, line 74]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 3 [file ffbonded.itp, line 75]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)

ERROR 4 [file ffbonded.itp, line 76]:
Incorrect number of atomtypes for dihedral (4 instead of 2 or 4)"

[ dihedraltypes ]
; Combined Bending-Torsion Coefficients
; i j k l func CBT coefficients (kJ/mol)
C2H4 C3H6A CHCH C3H6A 11 0.06089 -0.06511 -0.01607 0.00987 0.07594
2CHOCO 1CH2OCO C3H6E C3H6 11 0.06755 -0.04229 0.02886 -0.05563 0.01185
2CHOCO 3CH2OCO C2H4E C3H6 11 0.01193 -0.01743 0.06812 -0.05310 0.00788
1CH2OCO 2CHOCO C2H4E C2H4 11 0.06344 0.05895 0.06642 -0.04529 0.01282