Subject: Re: CCL:pressure scaling

From: Rick Venable <rvenable.-at-.pollux.cber.nih.gov>
Date: Tue, 23 Mar 2004 18:31:33 -0500

On Tue, 23 Mar 2004, Lubos Vrbka wrote:
> could someone explain to me how the isotropic and nonisotropic
> pressure scaling in molecular dynamics work?
>
> can i make big mistake if i use isotropic scaling (nonisotropic is not
> yet supported by pmemd) for non-isotropic system (solid-liquid
> interface)?

It is an issue for liquid:liquid interfaces; see

COMPUTER-SIMULATION OF LIQUID/LIQUID INTERFACES. 1. THEORY AND
APPLICATION TO OCTANE/WATER
ZHANG YH, FELLER SE, BROOKS BR, PASTOR RW
J CHEM PHYS 103 (23): 10252-10266 DEC 15 1995

See the discussions of NPAT and NPgammaT ensembles in the above
reference.  If there's a surface tension, it could be an issue for a
solid:liquid interface as well, but it may depend on details of the
solid phase model.

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Rick Venable           29/500
FDA/CBER/OVRR Biophysics Lab
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