argon.itp

[ moleculetype ]
AR        3    

[ atoms ]
 ; nr     type  resnr     resid      atom     cgnr   charge     mass
    1     AR        1        AR       AR1        0   0.0000  39.9480

[ pairs ]
;

[ bonds ]
;

[ angles ]
;

[ dihedrals ]
;

[ dihedrals ]
; improper dihedrals