[gpaw-users] Calculations in LCAO mode

[Ask Hjorth Larsen]

Hi

On Thu, 23 Feb 2012, Ulrik Grønbjerg wrote:

> Hi all
> 
> I have attached the txt-file. In this case it managed to converge the first
> SCF-cycle in 113 steps, but the second one failed to converge.
> 
> Best wishes
> Ulrik

A couple of comments.

  * Reduce linear mixing parameter to 0.03.  This should fix the
    convergence problem.  Larger systems may require lower values.

  * The Poisson solver is not the problem, so you can use the default
    convergence criterion.

  * Use gpts=h2gpts(h=0.18, atoms.get_cell(), idiv=8) to get a nicely
    divisible-by-large-power-of-2 grid (as opposed to the present one
    which is only divisible by 4).

  * Enable ScaLAPACK

  * (You can use more nodes and it should still be efficent due to
     k-points.)

Regards
Ask