Re: [ESPResSo-users] freeze during warmup integration

[Axel Arnold]

On 09/05/2012 08:20 PM, Nick Kinney wrote:
> I am trying to run a simple system (before I setup up a more complex 
> system) which consists of several polymers ~50 monomers each in a 
> spherical confinement.  I am using the PSAW to place the polymers. 
>  but then when I go to heat up the system by placing a cap on the LJ 
> potentials the program stops.  Just freezes and I have to cntr-c. 
>  some other strange observations if I change epsilon sometimes is will 
> get to the second warm step and then freeze.  Thirdly all my Lennard 
> Jones potentials in my observable file show negative energy, is this a 
> convention??  Thanks, Nick 
Hi Nick,

can you please post your script? There are many possibilities to get the 
simulation really slow, e.g. defining a simulation box of 1000x1000x1000 
sigma^3, setting the skin to almost half the box length,...

The negative LJ energy simply means that most particles are not 
overlapping, but are in the attractive tail of the LJ potential. If you 
would simulate in the NPT ensemble, this would mean that the box would 
like th shrink.

Axel

--
JP Dr. Axel Arnold           Tel: +49 711 685 67609
ICP, Universität Stuttgart   Email: address@hidden
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