Re: [ESPResSo-users] Question about simulation of water

[Xikai Jiang]

The SPC/E model treats water as a rigid molecule, and the O-H and H-H bonds are all rigid simulated by Rattle-Shake algorithm. According to the manual, section 8.1.22. Pressure, it mentions that the pressure contribution for rigid bonds is not included. I'm thinking will this cause the problem?

Best,

Xikai

> Date: Tue, 30 Sep 2014 21:45:15 +0200
> From: address@hidden
> To: address@hidden; address@hidden
> Subject: Re: [ESPResSo-users] Question about simulation of water
>
> Dear Fei,
>
> this is a well-known problem for solvent box equilibration.
> Increase the initial distance between the water molecules and start with
> a NVT simulation.
> NVT allows you to find a somehow equilibrated structure with a wrong
> density.
> After that and under consideration of the final NVT snapshot, you can
> probably perform some NPT without exploding pressure to achieve the
> correct density.
>
> Best regards,
> Jens
>
> On 09/29/2014 10:10 PM, Fei Zhang wrote:
> > Dear All,
> >
> > I am doing a simulation of pure water using Espresso now. However,
> > when I did the NVT simulation, the pressure always blow up. I used
> > SPC/E water model and used rigid bond for the bond between O and H.
> > Can anyone help me with this problem?
> >
> > The script is attached.
> >
> > Thank you.
> >
> > Fei
>
>
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