[Pw_forum] Yet another question about graphene bandstructure

[jbobak]

Hi all,
I've searched the forum for this question, but nobody seems to be having
quite the same issue, so I expect I'm doing something uniquely stupid. I
am trying to calculate the band structure of graphene (using Espresso
5.0.3) for practice before I use a more complicated system. I do an SCF
calculation with just the unit cell (2 atoms) with automatic k-points 18
18 1 0 0 0. Then I do a band structure calculation with k-points as
follows:

K_POINTS {tbipa}
7
0.00000 0.00000 0.00000 1
0.28868 0.16666 0.00000 1
0.57735 0.33333 0.00000 1
0.43301 0.41666 0.00000 1
0.28868 0.50000 0.00000 1
0.14435 0.25000 0.00000 1
0.00000 0.00000 0.00000 1

I then run bands.x, followed by plotband.x which I run interactively.
Everything works fine in that I get no errors, but the bandstructure plot
is wrong (see attached pdf). The bands should cross at the K point. I
think the problem has something to do with the k-points, which is why I
have reproduced them above, but I have also attached the relevant input
and output files. Could it be because the high-symmetry k-points I
selected are not present in the automatically selected grid?

Thank you so much for any help,
Julia Bobak

Research Assistant
University of Victoria, Victoria, BC, CANADA
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