Energy difference between CP2K and VASP energy calculation results of fcc Si

[brhr]

Dear CP2K experts,

I have a very rudimental (probably stupid) question.....

Energy of face centered cubic Si which calculated by VASP 
found at VASPwiki example page (
https://cms.mpi.univie.ac.at/wiki/index.php/Fcc_Si)
is -4.8758538 eV when the lattice parameter is 3.9 angstrom.

I also found fcc Si calculations at the CP2K tutorial pages.
 ( "Simple Static Energy and Force Calculation Using QUICKSTEP"(
http://www.cp2k.org/tutorials:static_calculation)
and "How To Converge The Multi-Grid Used in QUICKSTEP"(
http://www.cp2k.org/tutorials:converging_grid) )

Energy cutoff values, lattice parameters and XC functional are different 
between these VASP and CP2K cases,
and SCF_MAX is set to 1 in the case of CP2K.
So I calculated fcc Si energy with CP2K 5.1 setting the energy cutoff 240 
eV ~ 8.820 a.u., the lattice parameter 3.9 angstrom,
 XC functional PBE and SCF_MAX defaut value.

The input file is the following:
-----------------------------------------------------------------
@SET twice_lp 7.80

&GLOBAL
  PROJECT Si_bulk8
  RUN_TYPE ENERGY
  PRINT_LEVEL MEDIUM
&END GLOBAL
&FORCE_EVAL
  METHOD Quickstep
  &DFT
    BASIS_SET_FILE_NAME  BASIS_SET
    POTENTIAL_FILE_NAME  GTH_POTENTIALS
    &MGRID
      CUTOFF 8.820
    &END MGRID
    &QS
      EPS_DEFAULT 1.0E-10
    &END QS
    &SCF
      SCF_GUESS ATOMIC
      EPS_SCF 1.0E-6
      ADDED_MOS 10
      CHOLESKY INVERSE
      &SMEAR ON
        METHOD FERMI_DIRAC
        ELECTRONIC_TEMPERATURE [K] 300
      &END SMEAR
      &DIAGONALIZATION
        ALGORITHM STANDARD
      &END DIAGONALIZATION
      &MIXING
        METHOD BROYDEN_MIXING
        ALPHA 0.4
        BETA 0.5
        NBROYDEN 8
      &END MIXING
    &END SCF
    &XC
      &XC_FUNCTIONAL PBE
      &END XC_FUNCTIONAL
    &END XC
  &END DFT
  &SUBSYS
    &KIND Si
      ELEMENT   Si
      BASIS_SET DZVP-GTH-PBE
      POTENTIAL GTH-PBE-q4
    &END KIND
    &CELL
      SYMMETRY CUBIC
      A     ${twice_lp}    0.00    0.00
      B     0.00    ${twice_lp}    0.00
      C     0.00    0.00    ${twice_lp}
    &END CELL
    &COORD
      SCALED
      Si    0.00    0.00    0.00
      Si    0.00    0.50    0.50
      Si    0.50    0.50    0.00
      Si    0.50    0.00    0.50
      Si    0.75    0.25    0.75
      Si    0.25    0.25    0.25 
      Si    0.25    0.75    0.75
      Si    0.75    0.75    0.25
    &END COORD
  &END SUBSYS
  &PRINT
    &TOTAL_NUMBERS  ON
    &END TOTAL_NUMBERS
  &END PRINT
&END FORCE_EVAL
-----------------------------------------------------------------

A part of the result by CP2K 5.1 is
-----------------------------------------------------------------
SCF WAVEFUNCTION OPTIMIZATION

  Step     Update method      Time    Convergence         Total energy    
Change
  
------------------------------------------------------------------------------
     1 NoMix/Diag. 0.40E+00    0.2     3.06132393       -28.5675142867 
-2.86E+01
     2 Broy./Diag. 0.40E+00    0.3     2.32214549       -28.7998050659 
-2.32E-01
     3 Broy./Diag. 0.40E+00    0.3     0.58522732       -29.4698863750 
-6.70E-01
     4 Broy./Diag. 0.40E+00    0.3     0.20998859       -29.2828168394  
1.87E-01
     5 Broy./Diag. 0.40E+00    0.3     0.12057075       -29.1932153866  
8.96E-02
     6 Broy./Diag. 0.40E+00    0.3     0.05618396       -29.1361561613  
5.71E-02
     7 Broy./Diag. 0.40E+00    0.3     0.01016729       -29.1363881842 
-2.32E-04
     8 Broy./Diag. 0.40E+00    0.3     0.00251115       -29.1338276656  
2.56E-03
     9 Broy./Diag. 0.40E+00    0.3     0.00053053       -29.1364584302 
-2.63E-03
    10 Broy./Diag. 0.40E+00    0.3     0.00012439       -29.1370164369 
-5.58E-04
    11 Broy./Diag. 0.40E+00    0.3     0.00008751       -29.1372252303 
-2.09E-04
    12 Broy./Diag. 0.40E+00    0.3     0.00001301       -29.1371970535  
2.82E-05
    13 Broy./Diag. 0.40E+00    0.3     0.00001000       -29.1371543754  
4.27E-05
    14 Broy./Diag. 0.40E+00    0.3     0.00000033       -29.1371468686  
7.51E-06
  *** SCF run converged in    14 steps ***

  Electronic density on regular grids:        -32.0116716966       
-0.0116716966
  Core density on regular grids:               32.0008931651        
0.0008931651
  Total charge density on r-space grids:       -0.0107785315
  Total charge density g-space grids:          -0.0107785315

  Overlap energy of the core charge distribution:               
0.00000000000000
  Self energy of the core charge distribution:                
-82.06393942512820
  Core Hamiltonian energy:                                     
15.15717724613789
  Hartree energy:                                              
46.02547467061829
  Exchange-correlation energy:                                 
-8.25223104355429
  Electronic entropic energy:                                  
-0.00362831666283
  Fermi energy:                                                
-0.03620657710631

  Total energy:                                               
-29.13714686858875
-----------------------------------------------------------------

The obtained energy per atom is -29.13714686858875 / 8 = 
-3.64214335857359375 a.u. ~ -99.10776 eV
This is very different from -4.8758538 eV.

Could anyone interpret the difference between these results?
Thank you in advance.

brhr 
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