[Pw_forum] PBE0 convergence

[Jie Jiang]

Dear PWscf,

I get a problem in PBE0 convergence. Below is part of the input file,

&CONTROL
  calculation  = "scf",
/
&SYSTEM
  ibrav     = 12,
  celldm(1) = 15.73981,
  celldm(2) = 0.62519,
  celldm(3) = 4.39673,
  celldm(4) = 0.62519,
  nat       = 58,
  ntyp      = 5,
  ecutwfc   = 80.0,
  input_dft = 'pbe0',
  nqx1 = 2, nqx2 = 1, nqx3 = 1,
  exxdiv_treatment= 'gygi-baldereschi'
  ecutvcut = 0.7
  x_gamma_extrapolation= .TRUE.
  occupations = "smearing",
  smearing    = "methfessel-paxton",
  degauss     = 0.01,
/
&ELECTRONS
  conv_thr    = 1.D-6,
  mixing_beta = 0.5D0,
/
ATOMIC_SPECIES
C     12.0107
S     32.066
H     1.00794
O    15.9994
Zn   65.409
/
K_POINTS {automatic}
 6 3 1 0 0 0

The output 'dexx' is

     est. exchange err (dexx)  =       0.00059720 Ry
     est. exchange err (dexx)  =      -0.02431459 Ry
     est. exchange err (dexx)  =      -0.02596414 Ry
     est. exchange err (dexx)  =      -0.02720608 Ry
     est. exchange err (dexx)  =      -0.02821286 Ry
     est. exchange err (dexx)  =      -0.02946368 Ry
     est. exchange err (dexx)  =      -0.03148666 Ry
     est. exchange err (dexx)  =      -0.03481403 Ry
     est. exchange err (dexx)  =      -0.03964928 Ry
     est. exchange err (dexx)  =      -0.04531623 Ry

and Fock energy is

-177.9185854736362
-177.9185854736362        -177.8610717829301        -177.8047524875259
-177.8047524875259        -177.8356769333793        -177.8179722072562
-177.8179722072562        -177.8457748551563        -177.8216492155755
-177.8216492155755        -177.8490273372818        -177.8219932983469
-177.8219932983469        -177.8500300290520        -177.8216410368603
-177.8216410368603        -177.8505498629616        -177.8205313239625
-177.8205313239625        -177.8511288881755        -177.8187531280260
-177.8187531280260        -177.8519180436694        -177.8154548907789
-177.8154548907789        -177.8530355735678        -177.8113176980133
-177.8113176980133        -177.8542927054368        -177.8066352532881

Can you please help me in this issue.

Thanks,

Jie Jiang

Applied Physics
Yale University
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