[Wien] MgO Ghostbands - when do they matter

[Peter Blaha]

> I found the solution for this particular case, and it is slightly
> at odds with the UG (although there is a minor mention for TiO2
> on p153). It was to use a larger RMT for MgO (1.9) and a smaller
> one for O (1.6).

This is not really my recommendation. Spheres should be "equal" for s,p
elements, only for d-elements (Ti) they should be larger. (see faq page
on how to select RMT)

For your problem: Usually you can forget a QTL-B value of 1. These are
NOT ghostbands, but slightly enhanced values for the u-dot contribution.
I would start worrying for values of 5 and above.

It is most likely because of some shallow semicore states (Mg 2p or O 2s)
and it depends on RMT whether or not an E-TOP is found or not. If not, it
keeps the linearization energy at the defaul value and this might not be
optimal.

You may try:   run_lapw -in1new 1

But please note: after that ALWAYS use the -in1new switch (or change back
explicitly with -in1old

Regards

> > 	Onderwerp: [Wien] MgO Ghostbands - when do they matter
> >
> >
> >
> > 	I am trying to run a set of calculations varying the
> > 	lattice parameter of MgO by -10 to +30%. I keep running
> > 	into ghostbands, with a QTL of around 1. At what level
> > 	does this matter. If anyone can suggest specific strategies
> > 	to try (not RKMAX, GMAX or the # of LM) I would be interested,
> > 	particularly if they are general.
> >
> >
> > 	-----------------------------------------------
> > 	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:ldm at risc4.numis.northwestern.edu
> > 	http://www.numis.northwestern.edu
> > 	Nanocrystallography Workshop, http://ncem.lbl.gov/workshop.htm
> > 	-----------------------------------------------
> >
> >
> > 	_______________________________________________
> > 	Wien mailing list
> > 	Wien at zeus.theochem.tuwien.ac.at
> > 	http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> >
> >
> >
> >
>
> -----------------------------------------------
> 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:ldm at risc4.numis.northwestern.edu
> http://www.numis.northwestern.edu
> Nanocrystallography Workshop, http://ncem.lbl.gov/workshop.htm
> -----------------------------------------------
>
>
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> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
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>


                                      P.Blaha
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Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
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