[Wien] question about ISPLIT and orbital degeneracy

[Georg Eickerling]

Dear WIEN users,

I have a question concerning the ISPLIT option:
Assuming a cubic (non-magnetic/non spin-polarized) NiO as example,
the default ISPLIT after init_lapw is "2" which results in the
expected eg/t2g splitting of the Ni d-orbitals in the projected DOS.

What I now did was

change ISPLIT to 8
run lapw2 -qtl (or qtl itself with QSPLIT 2)

in order to see the same eg/t2g degenracy for the five individual
d-orbitals. However, this produces a partial d-DOS in which none of
the orbitals are degenerate.

I only obtain the correct degeneracy with ISPLIT 8/QSPLIT 2 when
first calculating a "P1" k-list by

removing all symmetry operations apart from the identity from the struct
generating a new klist
run lapw1
run lapw2 -qtl (or qtl itself)

So my question is: Why do I need the "P1" k-list in this case,
should not the eigenvalues on the original k-points show the
degeneracies as well?

Thank you in advance for your help,

Georg Eickerling




-- 
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Dr. Georg Eickerling
Universitaet Augsburg
Institut fuer Physik
Lehrstuhl fuer Chemische Physik und Materialwissenschaften
Universitaetsstr. 1
86159 Augsburg

E-Mail:	georg.eickerling at physik.uni-augsburg.de
Phone:	+49-821-598-3362
FAX:	+49-821-598-3227
WWW:	http://www.physik.uni-augsburg.de/cpm/
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