Re: [ESPResSo-users] Error with salt.tcl

[Axel Arnold]

On Tuesday 26 April 2011 10:11:02 gerd wrote:
> Hallo everybody,
> 
> can you help me, i am a beginner.
> 
> My first script stops with the
> error-message:
> 
> P3M tune parameters: Accuracy goal = 1.00000e-02
> System: box_l = 6.586337560083495, # charged part = 200 Sum[q_i^2] = 200.0
> failed to tune P3M parameters to required accuracy
>     while executing
> "inter coulomb 10.0  p3m tunev2   accuracy 1e-02  mesh 32"
>     (file "salt.tcl" line 21)

Well, P3M can't reach the desired accuracy. The example in the users' guide 
was always at the limit; with Es 3.0.0, we changed the P3M tuning a bit, it is 
more strict now, and fails. You can either choose a lower Bjerrum length, by 
that making the system less frozen, or to reduce the accuracy to 1e-1.

Note that your script still will crash - you put the warm up / force capping 
after the integration, so that the integration immediately starts with full 
interactions.

Axel

-- 
Dr. Axel Arnold Tel: +49 711 685 63593
ICP, Universität Stuttgart      Email: address@hidden
Pfaffenwaldring 27
70569 Stuttgart, Germany