[Pw_forum] GaAs Band structure

[nand]

Sir,
I am a research scholar at the Ranchi university, India. It will be a
great help if you can help me with the band structure calculation for
GaAs using Quantum Espresso.

I do not get the correct band structure  even with the input file you  mentioned below. I am attaching the band structure pdf file which I
produced using  input file given below. As you can see that the fermi level is
wrongly located and the band gap is badly  underestimated. Please tell
me about the possible fault(s) possible in my calculation.

Thanking you in advance.
Nand Rana,
(Research Scholar)
Ranchi, India.  
-----------------------------------
input file for the scf calculation:

&control
  calculation='scf',
  outdir='./tmp',
  prefix='gaas',
  pseudo_dir='/espresso-4.0.4/pseudo'
/

&system
  ibrav=2,
  celldm(1)=10.6827,
  nbnd=8,
  nat=2,
  ntyp=2,
  ecutwfc=40.0d0,
  occupations='fixed',
  nspin=1
/

&electrons
  conv_thr=1d-6,
  mixing_beta=0.7,
  diagonalization='david'
/

ATOMIC_SPECIES
 Ga   69.723   Ga.pz-bhs.UPF
 As   74.92160 As.pz-bhs.UPF

ATOMIC_POSITIONS  alat
  Ga 0.0   0.0   0.0
  As 0.25  0.25  0.25

K_POINTS   automatic
   10 10 10 0 0 0







      
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