[Wien] Question about hand-made structure calculation

[B. Yanchitsky]

Cara Watson wrote:
> Dear Wien2k users,
> What's more, I continued running initialization and ignoring the
> warnings from "sgroup" and "symmetry" (and I rejected any structure
> change generated by NN, sgroup, etc), at the end I was able to run the
> SCF calculations. However, the generated bandstructure is totally
> different (or at least mostly different) from the one got from the
> ICSD bismuth data which had specified R-3m symmetry. And what's even
> worse, the calculated total energy is around -258978.490839 Ry
> compared to the actual total energy around -86326.201472 Ry. It seemed
> the calculation turned out to be a total failure.
> 

You may ignore warnings from sgroup, but symmetry clearly
says through case.outputs that structure is wrong,

  ---------- ERROR ------------------
   The (multiplicity of this atom)*(number of pointgroup-operations) is NOT
   = (number of spacegroup-operations)

this is not a warning, you can not proceed further with such errors.
You have to use rhombohedral setting
(2 atoms) but not hexagonal (6 atoms), because wien does not understand
atomic positions that come from translation vectors, in this case
(2/3,1/3,1/3)+ and (1/3,2/3,2/3)+.
Take care on numbers like 2/3 and 1/3, in structure file they are represented
as 0.66667000 and 0.33333000, this may confuse software,
use instead all 8 digits, i.e. 0.66666667 for 2/3 and 0.33333333 for 1/3.
Similar for number 0.56733000, here must be 0.56733333 according to space group
R-3m, because 0.23400000+1/3=0.56733333 not 0.56733000, this might result
to identification of space group for your structure as #164 P-3m, not as  #166 R-3m.

There are 2 files in attachment, the first is corrected input file, the
second is produced by sgroup and corrected a bit by hands,
last digit for some coordinates has been lost.

Regards,
Bogdan Yanchitsky

Institute of Magnetism
Vernadsky Blvd., 36-b
03142  Kiev
UKRAINE

Tel. (+380-44) 444 34 20
Fax. (+380-44) 444 10 20
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