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[Kristopher Andersen <andersen@yclept.ucdavis.edu>]

I'm puzzled by the Fermi energy in ABINIT. I've been running some
calculations on ZnSe and for the band energies at k = 0 I get

 kpt#   1, nband= 10, wtk=  0.00800, kpt=  0.0000  0.0000  0.0000
  -0.53351  -0.29563  -0.29563  -0.29563  -0.28408  
  -0.28408  -0.05693  -0.05693  -0.05693  -0.01967

The Fermi energy isn't printed out anywhere in the output file, but is
supposedly written to the unformatted _WFK and _DEN files. When I look
there, they both give the Fermi energy (variable fermie) to be 0.0?
Clearly this would be in the conduction band given the band energies
above, since ZnSe has 9 occupied bands and is a direct gap
semiconductor.

Is it true that ABINIT is predicting ZnSe to be a metal or am I just
not reading the Fermi energy right? Why isn't the Fermi energy printed
out in the output file somewhere? Maybe it is and I'm missing it?

Thanks for the help. For reference, the benign input file for this
calculation is

########################################################################
# ZnSe.scf
#
# Crystalline ZnSe, zincblende crystal structure
# 
# Goes through the self-consistent cycle and outputs the ground state
# charge density and wavefunctions.
########################################################################

ixc  11                  # PBE GGA functional
ecut 45.0                # planewave cutoff energy (Hartree)

# k-point grid
kptopt  1                # automatic generation, using symmetry
nshiftk 1
shiftk  0.0 0.0 0.0
ngkpt   5 5 5            # Monkhorst-Pack grid (odd to include gamma)

# unit cell
acell 3*10.9118          # scaling parameters for primitive vectors
rprim  0.0  0.5  0.5     # FCC primitive vectors
       0.5  0.0  0.5   
       0.5  0.5  0.0

# specify atoms
ntype 2                  # 2 types of atoms (Zn, Se)
zatnum 30 34             # type 1 = Zn; type 2 = Se
natom 2                  # 2 atoms in the unit cell
type 1 2                 # atom 1 = Zn; atom 2 = Se
xred                     # atomic positions are given in reduced coordinates
   0.0  0.0  0.0           # reduced coordinates of atom 1 (Zn)
   0.25 0.25 0.25          # reduced coordinates of atom 2 (Se)

# SCF parameters
nstep  25                # maximum number of SCF cycles
tolvrs 1.0d-6            # tolerance on the potential (Hartree)
diemac 12.0              # model dielectric constant (for preconditioning)
prtden 1                 # output the charge density

-- 
Kristopher Andersen               http://yclept.ucdavis.edu/~andersen
Department of Physics                    andersen@physics.ucdavis.edu
University of California at Davis                   +1 (530) 752-0446