[gmx-users] charmm27 in gromacs- grompp error

[Revthi Sanker]

Dear all,
I am using charmm27 forcefield in gromacs for performing all atom simulations (system comprising of DOPC, cholesteryl ester and protein) .I got the itp file for dopc from the lipid book in which they have mentioned #include "charmm27.ff/ffbonded.itp" and  "charmm27.ff/ffnonbonded.itp" to source to these for the parameters of each bond, angle dihedral etc based on the atom types instead of mentioning explicitly each numerical value from the gromacs directory.But it could not read the file and displayed:

Syntax error - File ffbonded.itp, line 2 Last line read: '[ atomtypes ]' Invalid order for directive defaults

 When I commented those lines and again ran grompp, it generated the following error:
  No default Angle types
No default Ryckaert-Bell. types.

Kindly suggest me in this issue.

Earnestly awaiting a reply,

Revathi
​M.S. Research Scholar
Indian Institute Of Technology, Madras
India