[gmx-users] Dihedral multiplicity

[David van der Spoel]

On Tue, 30 Apr 2002, Xavier Periole wrote:

>
>Hi all,
>
>I wanted to modify the multiplicity of a proper dihedral angle
>in the topol.top file. I rapidly figured out that is not possible
It is quite trivial, just add new parameters for the particular dihedral.
You will have to add all parameters, and if you change the multiplicity
you have to  add the params twice. This is because grompp interprets a
difference between the parameters you give and those in the database as
input for free energy perturbation, and while you can change the force
constant and phase angle you can not change the multiplicity.


Groeten, David.
________________________________________________________________________
Dr. David van der Spoel, 	Biomedical center, Dept. of Biochemistry
Husargatan 3, Box 576,  	75123 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://zorn.bmc.uu.se/~spoel
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