[gmx-users] inserting a new potential

[David L. Bostick]

Hi,

Aren't directives in the mdp file called "acc_grps" and "accelerate" where
you can give a constant acceleration to any set of atoms in the system?....
That is, if you want to model gravity in the approximation that
acceleration due to gravity is constant.

If you want the classical 1/r^2
force, I would imagine that you could rig the coulomb interaction to do
this by giving fake charges to all the particles, provided you didn't want
any of the atoms to be charged... that is..
you don't want an electrostatic interaction AND a gravitational
interaction.  This sort of thing wouldn't make sense anyway, because
gravity dominates on the large scale and electrostatics dominate on the
small scale.


David
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David Bostick					Office: 262 Venable Hall
Dept. of Physics and Astronomy			Phone:  (919)962-0165
Program in Molecular and Cellular Biophysics
UNC-Chapel Hill
CB #3255 Phillips Hall				dbostick at physics.unc.edu
Chapel Hill, NC 27599	           		http://www.unc.edu/~dbostick
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On Thu, 24 Jul 2003, Alan Wilter Sousa da Silva wrote:

>
> Hi List!
>
> Despite what I've read in gmx manual 3.1.1 about defining a different
> potential function (p. 122), I don't think it would serve to me.  I would
> like to insert a new force like gravitational field derived, i.e.,
> unidirectional and acting over all atoms of simulation.
>
> If I have to handle the code, from where should I have to start?
>
> Any suggestion would be very welcome.
>
> BTW, I'll do my homework looking at the code to get familiar.
>
> Cheers,
>
> --
> -----------------------
> Alan Wilter S. da Silva
> -----------------------
>  Laboratório de Física Biológica
>   Instituto de Biofísica Carlos Chagas Filho
>    Universidade do Brasil/UFRJ
>     Rio de Janeiro, Brasil
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