[Wien] Energy gap zero in outputtrance file of Boltztrap calculation

[saurabh singh]

Dear Wien2k users,

I am using wien2k 14.2 version. I performed the LDA+U calculation
(runsp_lapw -orb -cc 0.0001)  for the ZnV2O4 compound (using tetragonal
Antiferromagnetic structure file) with k point 40X40X40. I obtained the
required energy and charge convergence criteria. In the case.scf file the
value of fermi energy is 0.4903644 Ry. In the case.scf file and the total
DOS calculation it shows there is energy gap of 0.330 eV (i.e. .0242 Ry)
about the fermi energy.  Using the case.energyup/dn file I calculated the
transport properties using Boltztrap code (x_trans BoltzTraP -up -orb). The
intrans file used for the calculation is as follows:

WIEN                                       # Format of DOS. Either WIEN for
to use WIEN like case.struct and case.energ
1 0 0 0                                     # isetfermi idebug setgap
gapchange
0.49036  0.0005 0.4 136.0000    # Fermilevel (Ry), deltae, ecut, number of
valence electrons
CALC                                       # CALC (calculate expansion
coeff, Eq.(p1), NOCALC (read from file)
5                                            # lpfac, number of latt-points
per k-point
BOLTZ                                    # run mode (only BOLTZ is
supported)
0.15                                        # efcut. energy range of
chemical potential around efermi that is used
1400. 20.                                 # Tmax, temperature grid

-1.0                                        # Energyrange of bands given
individual DOS output sig xxx
TETRA                                  # scheme to obtain DOS. HISTO/TETRA:
histogram/thetrahedron[4] sampling
#0 0 0 0 0                              # τ -model. Not documented
#2                                         # number of fixed dopings
#1E20 -1E20                         # fixed doping levels in cm−3


after the boltztrap calculation there is no gap obtained in
case.outputtrans file. If I used the value of Fermienergy a bit more in the
intrans file which lies in the band gap as observed in DOS plot, still we
don't get any gap in the case.outputtrans file. May I know the reason why
we are unable to get the gap in outputtrans file. The below outputtrans
file is correspond to the fermienergy 0.49036, 0.49536 and 0.502100 Ry

1.
==============  OUTPUT from BANDANA       ================
Egap:     0.000000 Energy range:     0.037447 -     0.944497. Bands
range:   89 -  172
VBM:     0.490360 CBM:     0.490360 Efermi:     0.490360

2.

==============  OUTPUT from BANDANA       ================
Egap:     0.000000 Energy range:     0.037447 -     0.944497. Bands
range:   89 -  172
VBM:     0.495360 CBM:     0.495360 Efermi:     0.495360
-


3.
==============  OUTPUT from BANDANA       ================
Egap:     0.000000 Energy range:     0.037447 -     0.944497. Bands
range:   89 -  172
VBM:     0.502100 CBM:     0.502100 Efermi:     0.502100
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