<div>Dear Gmx Developer or Users,</div>
<div> </div>
<div>Can anyone explain which section is for the parameters of improper dihedral angle</div>
<div>on the file of ffbonded.itp ?</div>
<div> </div>
<div>On the file of ffbonded.itp, there is not any comment to differentiate the proper and improper</div>
<div>dihedral angle. </div>
<div> </div>
<div>E.g. on thie file of ffbonded.itp in the directory of charmm27.ff </div>
<div>There are two sections about dihedral angle:</div>
<div><br>[ dihedraltypes ]<br>; i j k l func phi0 cp mult<br>C CT1 NH1 C <strong> <font style="BACKGROUND-COLOR:#ffffff" color="#ff0000">9</font></strong><font style="BACKGROUND-COLOR:#ffffff" color="#ff0000"> </font> 180.00 0.8368 1<br>
......</div>
<div> </div>
<div>[ dihedraltypes ]<br>; i j k l func q0 cq<br>CPB CPA NPH CPA <strong> <font color="#ff0000">2</font></strong> 0.0000 174.0544</div>
<div>..........</div>
<div>There is also no explaination the explaination about the function type 2.</div>
<div> </div>
<div>It seems difficult for users to edit the parameters.</div>
<div>Thanks for the explainations!<br></div>