[Wien] band gap problem

[Lutz Rauscher]

Dear all,

I'm doing calculations on Mg2Sn, a semiconductor with a small indirect band
gap of about 0.3 eV. The calculations converge well, but the band gap is
underestimated significantly and valence and conduction band already overlap
slightly and I get a semimetal structure (attached).
I’m not sure how this influences the results (most important the dispersion
relation of the conduction band). How bad is it and is there a chance to
correct this somehow? Did I do something stupid?

Second question: I run into problems if I try to plot the band structure for
a super cell (105 bands). Ghostview plots about half of the structure and
then quits with the message: "gsapi_run_string_continue returns -101"
(whatever that means). Nevertheless, .spaghetti_ene looks good. Is there
another easy to use tool to plot the bands?

Thanks a lot! Lutz
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Mg2Sn Band eV.pdf
Type: application/pdf
Size: 17688 bytes
Desc: not available
Url : http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20031118/a7144076/Mg2SnBandeV.pdf