[Wien] Slab calculations

[Javad Hashemifar]

> It seems to me that, until you get a handle on the SCF convergence,
> you should reduce Rkmax considerably, maybe down to 6, so that
> the calculations will go faster.  Later on, you can see how properties
> converge as a function of Rkmax.

Hello,
I think for MT sphere of 3 au RKmax=6 is too small.
about oscillation in energy, if the DIS parameter is decreasing in scf cycle I
think there is no problem and my slab calculations also shows energy
oscillation at the few first iterations.
but if there is DIS oscillation without any trend to convergency, then I think
the first trick that you can try is reducing mixing factor and if the problem
persist after using small mixing factor, increasing number of k-points may
solve this problem,
Bests,
Javad Hashemifar 

> > Hi Everybody,
> >
> > I am trying to do a 6 layer slab calculation of Mg(0001) and I get energy
> > oscillations in the scf cycle. I already used a Rkmax of 10 and gmax of 14.
> > Does anybody have experience for these kind of calculations? What is the
> > crucial parameter to reach convergence? I have not optimized the positions,
> > but this should not play a role for convergence, right?
> >
> > Thanks a lot
> >
> > Mg MT sphere: 3
> > unit cell: 25 angstroem
> > vacuum thickness 12 angstroem



=====
-------------------------------------------------------------------------------
Javad Hashemifar                                      phone : ++49-30-8413 4804
Permanent : Physics Department, Isfahan University of Technology, Isfahan, Iran
Current : Fritz-Haber-Institut der MPG, Faradayweg 4-6, D-14195 Berlin, Germany
e-mails:  hashemi at fhi-berlin.mpg.de          &          hashemifar at ph.iut.ac.ir
-------------------------------------------------------------------------------

__________________________________
Do you Yahoo!?
Yahoo! Finance Tax Center - File online. File on time.
http://taxes.yahoo.com/filing.html