[CP2K:953] SCF goes wrong in QMMM after 37000 steps

[Teodoro Laino]

On 16 Apr 2008, at 13:50, Csilla Varnai wrote:

>
> Dear All,
>
> I'm running a QMMM simulation for 32 water molecule box with 1 qm
> molecule, NVE. The energy is not conserved, goes up gradually. Between
This is a quite strong claim.. do you have any experience with the  
CP2K QMMM module?

> steps 37186th and 37270 at several steps the SCF goes wrong. It does
> not converge in 50 steps, the energy increases and then oscillates.
> Afterwards, it seems to be fine until 40000th step.
> The QM cell is 10x10x10 Angstrom, density cutoff 300 Ry, time step 0.5
> fs, temperature 300 K. As for the SCF, I'm using the default
> parameters. MAX_ITER is 50. For the other steps, SCF never required
> more than 20 steps except a few ones, in which case it still remained
> below 31. Any idea why the SCF went wrong?
No.. and you rarely will get some help unless you won't post your  
full input file.

Cheers
Teo

> Thanks very much,
>
> Csilla
>
> >