[Wien] Convergence trouble with Spin Orbit calculation

[L. D. Marks]

Reduce f_pw in case.inm (latest version of mixer) to a value of ~ 0.1;
this is more important in most cases than reducing the BROYD term. Also,
check the Plane Wave convergence via "grep -e :PLANE case.scf", this
is often more important than :DIS.

Plausible case.inm for such a case:

BROYD 0.d0 YES (PRATT/BROYD, background charge (+1 for additional e), NORM
0.2 		MIXING FACTOR
0.15 1.5 	Scaling for PW and CLM coefficients, respectively
20 999 		nbroyd nuse

On Thu, 9 Sep 2004, Kirk Feindel wrote:

> Hi,
>
> I'm a relatively new user of WIEN2k and have spent some time determining convergence criterion for several lanthanum halide systems.  Of particular interest is the La EFG.
>
> For the lighter halide systems the EFG parameters agree very well with experiment.  Agreement for systems with the heavier halides is not good.  The first step, I presumed to remedy the problem would be to include spin orbit effects.  So, after convergence of a non spin orbit calculation I generate the necessary input files using initso_lapw, edit in the case.inso to include both atoms and run the calculation with run_lapw -so -ec 0.0001.
>
> The charge appears to want to converge, but the energy seems to oscillate or slowly decrease approaching no less than 25.
>
> I've tried inceasing the emax window in case.in1 to 5, and have also tried reducing the mixing factor in the case.inm.
>
> Clearly I'm not sure as to what I should be attempting.
>
> Suggestions?
>
> Any comments will be greatly appreciated.
>
> Kirk
>
> *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *
> Kirk Feindel
> E3-48 Gunning/Lemieux Chemistry Centre
> University of Alberta
> Edmonton, AB  T6G 2G2
> *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *

-----------------------------------------------
Laurence Marks
Department of Materials Science and Engineering
MSE Rm 2036 Cook Hall
2225 N Campus Drive
Northwestern University
Evanston, IL 60201, USA
Tel: (847) 491-3996 Fax: (847) 491-7820
mailto:L-marks at northwestern.edu
http://www.numis.northwestern.edu
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