In a nutshell, yes dihedral type 2 is for the IMPR charmm dihedrals and 9 is for the normal dihedrals. I think David or someone else added code to specifically support charmm dihedrals in this way.
On 2012-02-14 09:32:37PM -0600, Tom wrote: > Dear Gmx Developer or Users, > > Can anyone explain which section is for the parameters of improper > dihedral angle > on the file of ffbonded.itp ? > > On the file of ffbonded.itp, there is not any comment to differentiate the > proper and improper > dihedral angle. > > E.g. on thie file of ffbonded.itp in the directory of charmm27.ff > There are two sections about dihedral angle: > > [ dihedraltypes ] > ; i j k l func phi0 cp mult > C CT1 NH1 C * 9* 180.00 0.8368 1 > ...... > > [ dihedraltypes ] > ; i j k l func q0 cq > CPB CPA NPH CPA * 2* 0.0000 174.0544 > .......... > There is also no explaination the explaination about the function type 2. > > It seems difficult for users to edit the parameters. > Thanks for the explainations! > -- > gmx-users mailing list [email protected] > http://lists.gromacs.org/mailman/listinfo/gmx-users > Please search the archive at > http://www.gromacs.org/Support/Mailing_Lists/Search before posting! > Please don't post (un)subscribe requests to the list. Use the > www interface or send it to [email protected]. > Can't post? Read http://www.gromacs.org/Support/Mailing_Lists -- ================================================================== Peter C. Lai | University of Alabama-Birmingham Programmer/Analyst | KAUL 752A Genetics, Div. of Research | 705 South 20th Street [email protected] | Birmingham AL 35294-4461 (205) 690-0808 | ================================================================== -- gmx-users mailing list [email protected] http://lists.gromacs.org/mailman/listinfo/gmx-users Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/Search before posting! Please don't post (un)subscribe requests to the list. Use the www interface or send it to [email protected]. Can't post? Read http://www.gromacs.org/Support/Mailing_Lists
