[gmx-users] (no subject)

[David van der Spoel]

On 1 Jan 2003 pqchen at eyou.com wrote:

>Dear David:
>  From the literature I know the torsion parameters of NA-CW-CT-CT in
>fourier form is V1=2.344 kcal/mol, V2=-0.076 kcal/mol, V3=-1.224 kcal/mol,but
>I
>don't know the parameters of V0. So I can't sucessfully translate the OPLS
>parametes to RB parameters.
>  Can I use the fourier form parameters in the topol file?
>  For example:
>; ai   aj   ak  al funtc  .................
>  NA   CW   CT  CT  1     0.000  9.814   1  180.000  -0.318   2	0.000  5.125  
>3

It looks superficially OK, but when you don't have V0 it is problematic.
Of course it can be zero. Try plotting the potential if nothing else helps

David.