[gmx-users] Incorrect dihedral restraints

[Jonathan Khao]

Hello 
        
        My goal is to make dihedral restraints on the backbone of a bent
        alpha
        helix to obtain its original structure. I've looked through the
        mailing
        list, followed the instructions, applyed some dihedrals around
        57° but
        the obtained dihedrals are all close to 180°. 
        
        in my Top file, i have included the following lines
        [ dihedral_restraints ]
        ; A  B  C   D    type   label   angle  delta   kfac    pow
         56 58  60  73     1      6     -63.5   0       1       2
         73 75  77  78     1      7     -57.6   0       1       2
        
        and in the mdp file :
        dihre                    = Simple
        dihre-fc                 = 100
        dihre-tau                = 0
        nstdihreout              = 100
        
        What am i doing wrong ?
        
        Thanks !
        
        Jonathan Khao