[gmx-users] Help about 2 D periodic boundary condition

[David]

On Mon, 2003-01-13 at 21:58, David L. Bostick wrote:
> > I have also played a bit with epsilon_surface in water simulations. If
> > you use the value you put in for epsilon_surface for computation of the
> > dielectric constant (g_dipoles -epsilonRF epsilon_surface) you get the
> > same dielectric constant in all cases. However the Debye relaxation time
> > (which happens to be roughly correct fo SPC/E with tin-foil BC) is
> > ruined by using epsilon_surface not infinity. This makes me a bit
> > suspicious... Or is there a correction for this too?
> 
> Ok, that's difficult.  I don't believe I can answer that, but again, when
> you set epsilon_surface, it is for r->infinity from the central simulation
> cell.  It is difficult to say how different dielectric constants affect
> things.  The JCP I cited in the previous message about dielectric constant

I'm getting old... Paul van Maaren just pointed out to me that the
answer to my question is in a paper of ours from 1998
(JCP 108, 10220, 1998). Thanks for your comments anyway.

-- 
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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