[CP2K:764] Re: nose thermostat

[Teodoro Laino]

Ciao Diederica,

>
> These are added, as an attachment this time

Thanks.. will look into this problem ASAP.

> I'm modelling an isolated molecule, it should fit in the box. Using  
> NVE without temperature rescaling, with an analogue structure, an  
> energy drift was observed, that got worse after about 20 ps, though  
> no non-convergence was observed. The input file and an energy-plot  
> are added.
If you have a drift with NVE this means that energy and forces are  
not consistent.. or (what I assume) that the cutoff for the coulomb  
interactions is not large enough..

Please put all of the  RC_COULOMB and RC_INTERACTION and RC_RANGE to  
50.0.
You've the problem that in your cell the standard range (24 bohr)  
does not fully cover the extension of your molecule (more than 26 bohr).
Use a larger box (30.0 Angstrom) and set the above keywords to 50.0  
bohr.
You should not see any jump in the energy (or drift)..

> The potential and kinetic energy are conserved indeed, but the  
> conserved quantity is not
Sorry to disprove you, but it is not possible that in an NVT you have  
kinetic and potential conserved, since the thermostat
is continuously exchanging energy with the system.  I't s a matter of  
concept.. we may discuss about the magnitude of the
thermostat energy.. but that's another story..

Cheers
teo



>
>
>
> For the next time, can you please put tables and input files as
> attachment (maybe .tgz) so that the formatting of mail readers are
> not changed and the input files not digested ? Thanks..
>
> Ciao,
> teo
>
> Thanks for helping!
>
> Greetz,
> Diederica
>
>
>
>
> >
> <mailcp2k.tgz>