[gmx-users] Charm forcefield error..Atomtype CR not found ..

[rama david]

Hi Gromacs Friends,

I wish to apply charmff 27 to my protein and ligand
I proceed in following way ..

1. I separate the protein and ligand by grep command
    then delete the ligand lne grom pdb file
2  I generate the topology of protein in gromacs
    using the pdb2gmx command
3   I generate the ligand topology by swissparam ,
4   I protein top , I added the line..


; Include ligand topology
#include "ligand.itp"

The ligand.itp generated by swissparam contain position restrain file in it

Ligand itp has following line.....
 1 CR   1  LIG C1      1  0.0000  12.0110
   2 CR   1  LIG C2      2  0.0000  12.0110
   3 CR   1  LIG C3      3  0.0000  12.0110
   4 CR   1  LIG C4      4  0.0000  12.0110
   5 CR   1  LIG C5      5  0.0000  12.0110
   6 CR   1  LIG C6      6  0.0000  12.0110
   7 CR   1  LIG CM      7  0.5030  12.0110
   8 NRP  1  LIG N       8 -0.8530  14.0067
   9 HNRP 1  LIG HN1     9  0.4500   1.0079
  10 HNRP 1  LIG HN2    10  0.4500   1.0079
  11 HNRP 1  LIG HN3    11  0.4500   1.0079
  12 HCMM 1  LIG H1     12  0.0000   1.0079
  13 HCMM 1  LIG H22    13  0.0000   1.0079
  14 HCMM 1  LIG H23    14  0.0000   1.0079
  15 HCMM 1  LIG H32    15  0.0000   1.0079
  16 HCMM 1  LIG H33    16  0.0000   1.0079
  17 HCMM 1  LIG H42    17  0.0000   1.0079
  18 HCMM 1  LIG H43    18  0.0000   1.0079
  19 HCMM 1  LIG H52    19  0.0000   1.0079
  20 HCMM 1  LIG H53    20  0.0000   1.0079
  21 HCMM 1  LIG H62    21  0.0000   1.0079
  22 HCMM 1  LIG H63    22  0.0000   1.0079
  23 HCMM 1  LIG HM2    23  0.0000   1.0079
  24 HCMM 1  LIG HM3    24  0.0000   1.0079
.
.
.

Now when I give the grompp command  I stuck with following error ...


Program grompp, VERSION 4.5.4
Source code file: /build/buildd/gromacs-4.5.4/src/kernel/toppush.c, line: 1166
Fatal error:
Atomtype CR not found

How to solve the error..
All suggestion are welcome..

Thank you in Advance...


Have a good day.!!!

With Best Wishes,
Rama David.