[CP2K:1000] harmonic restraint functional form

[Teodoro Laino]

Hi Ali,

On 6 May 2008, at 06:57, Ali wrote:

>
> Dear cp2k users,
>
> I just wanted to check this to confirm. As far as I can tell the
> functional form for the harmonic restraint within the MOTION% 
> CONSTRAINT
> %COLLECTIVE%RESTRAINT is:
>
you got it right.. the functional form used is this one:

> k(x-x_o)^2

I will add a comment in the input reference regarding the functional  
form.
Thanks for the feedback!

Ciao,
Teo

>
> and NOT (k/2)(x-x_o)^2.
>
> I am used to seeing the latter in most of functional forms for the
> harmonic potential but I guess the implementation is the former. This
> isn't a complaint but more so a check to make sure that this is true.
> In fact in all the sections (except the FORCEFIELD section where you
> can select the functional form depending on whether you use CHARMM or
> GROMOS), for example when one uses the ddap_constraints, the
> functional form for the harmonic potential is the latter of the above.
>
> Ali
> >