[gmx-users] Unknown bond_atomtype C2

[Nilesh Dhumal]

Hello,

I am getting "Unknown bond_atomtype C2" error for grompp.

I don't have C2 atom in my .itp file. Here I used the .itp file

; For parameters see J. Phys. Chem. A. 2002, 106, 1074-1080
; Derived from parsing of runfiles/alat.top.orig
;[ defaults ]
; nbfunc        comb-rule       gen-pairs       fudgeLJ fudgeQQ
;1               3               yes             0.5     0.5
; comb-rule 3 is square-root sigma, the OPLSAA version

[ atomtypes ]
; full atom descriptions are available in ffoplsaa.atp
; name  bond_type    mass    charge   ptype          sigma      epsilon
 opls_124   S   16    32.06000     0.312       A    3.56000e-01  1.65268e+00
 opls_125   O   8     15.99940    -0.556       A    2.93000e-01  1.17152e+00
 opls_126   CT  6     15.03500    -0.148       A    3.81000e-01  6.69440e-01
 opls_140   HC  1      1.00800     0.090       A    2.50000e-01  1.25520e-01


[ bondtypes ]
; i    j  func       b0          kb
S     O       1    0.1530   225936.0
S     CT      1    0.1800   100416.0
CT    HC      1    0.1110   134724.8


[ angletypes ]
;  i    j    k  func       th0       cth
  CT     S      CT      1    95.0      142.256
  CT     S      O       1   106.75     330.536
  S      CT     HC      1   111.3      192.8824
  HC     CT     HC      1   108.4      148.532


[ dihedraltypes ]
;  i    j    k    l   func     coefficients
; OPLS Fourier dihedraltypes translated to Gromacs Ryckaert-Bellemans form
; according to the formula in the Gromacs manual.
CT     S      CT     HC      3      1.35352   4.06057   0.00000  -5.41410 
 0.00000   0.00000 ; sulfide all-atom
 O     S     CT      HC      3      0.00000   0.00000   0.00000   0.00000 
 0.00000   0.00000 ; small ring

I am not using atom C2 in my bonded parameters.

Why I am getting this error.

I am using Gromacs VERSION 4.0.7.

Thanks

Nilesh