[Pw_forum] Temperature continuously going down in cp.x run

[vega lew]

Dear nicola,

thank you for you reply.

I got another question after reading you repy.

I random all the atoms that allowed to move during the simulation including
the upper half of the slab and the adsorbate on the surface.
I think what I want to see is the reaction on the surface. So should I only
random the adsorbate with the all the atoms in slab fixed?
Do you think this method will be more easy to achieve the desired
temperature?

By the way, during the NVE calculation, is there a command to keep the
energy of the system?

best

vega

On Sat, Nov 28, 2009 at 6:47 AM, Nicola Marzari <marzari at mit.edu> wrote:

> vega lew wrote:
> > Dear nicola,
> >
> > thank you suggestion.
> > I'll make the NVE calculation after random the ions.
> >
> > I wonder what temperature is demand for the NVE?
> > if the temperature is too high than the demanded temperature, should I
> > make the smaller random again?
> > For example, if the temperature is ~1000K after NVE, but the demanded
> > is 300K, should I make the random process again using smaller amprp(1~3)?
> >
> > thank you
> >
> > vega
>
>
> Correct. In NVE yuo have no option (of course) to set the temperature - you
> start froma distorted configuration, and the higher the potential energy
> of this inital
> configuration, the higher the average kinetic energy (i.e. temperature)
> of the
> equilibrated system.
>
> Very much worth experimenting with this, before moving on.
>
>             nicola
>
>
> --
> ---------------------------------------------------------------------
> Prof Nicola Marzari   Department of Materials Science and Engineering
> 13-5066   MIT   77 Massachusetts Avenue   Cambridge MA 02139-4307 USA
> tel 617.4522758 fax 2586534 marzari at mit.edu http://quasiamore.mit.edu
>
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-- 
==================================================================================
Vega Lew ( weijia liu)
Graduate student
State Key Laboratory of Materials-oriented Chemical Engineering
College of Chemistry and Chemical Engineering
Nanjing University of Technology, 210009, Nanjing, Jiangsu, China
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Email: vegalew at gmail.com
Office: Room A705, Technical Innovation Building, Xinmofan Road 5#, Nanjing,
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