[Pw_forum] How to set the ensemble when doing MD

[Lu Yunhao]

Sorry, my questions are somewhat confused. I just want to compare MD
calculations at different temperatures under Electric Field.  I am also
interested in what will happen if the total energy is constant (NVE). Do you
have some experience on this?

Now, my question (maybe the last one) is: 
If I set ion_temperature="not_controlled", the "tolp" and "nraise" are still
meaningful or have some other meanings?  

Many thanks.

Message: 2
Date: Tue, 09 Jun 2009 09:13:37 -0400
From: Axel Kohlmeyer <akohlmey at cmm.chem.upenn.edu>
Subject: Re: [Pw_forum] ??: How to set the ensemble when doing
	molecule
To: PWSCF Forum <pw_forum at pwscf.org>
Message-ID: <1244553217.5214.19.camel at zero>
Content-Type: text/plain

On Tue, 2009-06-09 at 16:17 +0800, Lu Yunhao wrote:
> It is possible to do MD with initial T=0K? it seems the tempw can not be
set
> to zero.

just set it to 0.1 or alike. that is pretty well the same thing.
if your system is of high potential energy, it doesn't matter,
if you system is not, the atoms won't move anyways. 

it is hard for me to see how you can get meaningful dynamics
out of the kind of setup you are describing, as your requirements
to the MD and the properties of the system seem to contradict
each other.

axel.


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