[gmx-users] form of the angle potential in ffgmx2bon.itp

[David van der Spoel]

On Thu, 2003-01-30 at 09:43, Markus O Kaukonen wrote:
> Dear all,
> 
> What is the meaning of angle terms in ffgmx2bon.itp ?
> (this is option 1 in pdb2gmx)
> 
> >[ angletypes ]
> >  ; i    j    k func       tHC         cth
> >   HO   OA    C    1   109.500     397.480
> >   HO   OA   C1    1   109.500     397.480
> 
> So is the angle energy, for example, for HO-OA-C triplet
> 
> A) 0.5*397.480*(current_angle_in_deg - 109.500)^2  [kJ/mol]
> 
Almost the above, but angles are converted to radians first.


-- 
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://xray.bmc.uu.se/~spoel
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