[gmx-users] dipole moment of molecule of trans and cis azobenzene ?

[David van der Spoel]

On 2010-08-26 18.59, Chih-Ying Lin wrote:
>
> Hi
> The partial charges of the trans and cis azobenzene are given as point
> charges lied on each atom center in my MD simulation.
>
>
and where do you get the charges from?

> It is supposed that the real molecule of trans-azobenzene has a lower
> dipole moment than the cis one. So, the real molecule of
> trans-azobenzene is supposed to be more hydrophobic than the cis one.
>
>
>
> However, in my MD simulation =>
> "The partial charges of the trans and cis azobenzene are given as point
> charges lied on each atom center."
> => Is my trans-azobenzene molecule structure more hydrophobic than the
> cis-one?
> => how can I calculate the dipole moment from the given partial charges
> for each atom?
>
mu = sum_i q r

Or g_dipoles.

>
> Thank you
> Lin
>
>
>
>


-- 
David van der Spoel, Ph.D., Professor of Biology
Dept. of Cell & Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:	+46184714205.
spoel at xray.bmc.uu.se    http://folding.bmc.uu.se