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Hi,
I am trying to obtain the band structure plot for wurtzite ZnO using the following input file. But the plot seemed to be wrong. please help where I am wrong.

# ZnO wurzite (hexagonal) structure
# Computation of the band structure.

ndtset 2

#Dataset 1 : usual self-consistent calculation
kptopt1 1 # Option for the automatic generation of k points,
# taking into account the symmetry
nshiftk1 1
shiftk1 0.0 0.0 0.5 # This choice of origin for the k point grid
# preserves the hexagonal symmetry of the grid,
# which would be broken by the default choice.

ngkpt1 6 6 6
prtden1 1 # Print the density, for use by dataset 2
toldfe1 1.0d-6 # This value is way too large for most realistic studies of materials

#Dataset 2 : the band structure
iscf2 -2
getden2 -1
kptopt2 -3
nband2 12
ndivk2 10 12 17 # 10, 12 and 17 divisions of the 3 segments, delimited
# by 4 points.
kptbounds2 0.0 0.0 0.0 ! G
0.06666 0.33333 0.5 ! H
0.66666 0.33333 0.0 ! K
0.0 0.0 0.0 ! G
0.0 0.5 0.0 ! M
0.0 0.5 0.5 ! L

tolwfr2 1.0d-12
enunit2 1 # Will output the eigenenergies in eV


#Definition of the unit cell
acell 6.52 6.52 9.826

angdeg 90. 90. 120.
spgroup 186

#Definition of the atom types
ntypat 2
znucl 8 30

#Definition of the atoms
natom 4
typat 1 1 2 2
xred 0.6667 0.3333 0.5000
0.3333 0.6667 0.0000
0.6667 0.3333 0.8750
0.3333 0.6667 0.3750

#Definition of the planewave basis set
ecut 20.0 # Maximal kinetic energy cut-off, in Hartree

#Definition of the SCF procedure
nstep 10 # Maximal number of SCF cycles
diemac 12.0




And pseudopotentials are : /Psps_for_tests/HGH/8o.6.hgh and /Psps_for_tests/HGH/30zn.2.hgh

Hello,

What do you mean by "the plot seemed to be wrong", maybe you could post your plot so that we can help you better. Besides, you are using a Zn pseudo with only 2 valence electrons which is quite low, you should add the d electrons in the pseudos maybe that's what you are referring to as "seemed to be wrong"

Also your kptbounds does not match your kptopt value : if kptopt is negative, its absolute value gives the number of segments used for the bandstructure (see http://www.abinit.org/documentation/helpfiles/for-v6.6/input_variables/varbas.html#kptopt) but you have 6 kptbounds (so you want 5 segments)... you should put kptopt -5 and change ndivk accordingly (see the documentation on this variable) or remove ndivk and use ndivsm instead (which is more easier to use than ndivk)

David