Hybrid functional calculation results show large difference with VASP

[Xiaoming Wang]

Hello,

I conducted PBE0 and HSE calculations on a cube of ~10*10*10 (perovskite). 
For comparison, I also did the calculations using VASP (gamma only). 
However, to my surprise, the band gap obtained by cp2k is about 0.5 eV 
(HSE)  and 0.8 eV(PBE0) smaller than by vasp. The vasp results agree well 
with literature. For the cp2k calculations, I have checked the convergence 
of the cutoffs and auxiliary basis sets. Since for my structure, the only 
available basis sets is DZVP within BASIS_MOLOPT, thus I could not find a 
way to increase the primary basis size. But I checked the PBE results with 
DZVP compared with those of VASP. The difference of the band gap is very 
small, say only 0.02 eV. So I think the DZVP basis set is OK for my system. 
The inputs of my calculations are as follows. Could anyone give me some 
suggestions?

HSE input:
--------------------------------------------------------------------
&GLOBAL
 PROJECT_NAME CsInAgCl
 RUN_TYPE ENERGY
 PRINT_LEVEL LOW
&END GLOBAL

&FORCE_EVAL
 METHOD QS
  &DFT
    BASIS_SET_FILE_NAME BASIS_MOLOPT
    BASIS_SET_FILE_NAME BASIS_ADMM
    BASIS_SET_FILE_NAME BASIS_ADMM_MOLOPT
    POTENTIAL_FILE_NAME GTH_POTENTIALS
    WFN_RESTART_FILE_NAME -PBE.wfn
    &QS
     EPS_PGF_ORB 1.0e-6
    &END
    &MGRID
      CUTOFF 250
      REL_CUTOFF 60
    &END MGRID
    &XC
      &XC_FUNCTIONAL
       &PBE
        SCALE_X 0.0
        SCALE_C 1.0
       &END PBE
       &XWPBE
        SCALE_X -0.25
        SCALE_X0 1.0
        OMEGA 0.11
       &END XWPBE
      &END XC_FUNCTIONAL
      &HF
       FRACTION 0.25
       &SCREENING
        EPS_SCHWARZ 1.0e-6
       &END SCREENING
       &INTERACTION_POTENTIAL
        POTENTIAL_TYPE SHORTRANGE
        OMEGA 0.11
       &END INTERACTION_POTENTIAL
       &MEMORY
        MAX_MEMORY 2400
        EPS_STORAGE_SCALING 0.1
       &END MEMORY
      &END HF
    &END XC
    &SCF
     #ADDED_MOS 2
      MAX_SCF 100
      EPS_SCF 1.0e-6
      CHOLESKY INVERSE
      SCF_GUESS RESTART
      &OT
       PRECONDITIONER FULL_ALL
       ENERGY_GAP 0.01
      &END OT
    &END SCF
    &AUXILIARY_DENSITY_MATRIX_METHOD
     METHOD BASIS_PROJECTION
     ADMM_PURIFICATION_METHOD MO_DIAG
    &END AUXILIARY_DENSITY_MATRIX_METHOD
    &PRINT
     &MO_CUBES
      WRITE_CUBE F
      NHOMO 1
      NLUMO 1
     &END MO_CUBES
    &END PRINT
  &END DFT
  &SUBSYS
    &CELL
      ABC [angstrom] 10.5345 10.5345 10.5345
      ALPHA_BETA_GAMMA [deg] 90 90 90
      PERIODIC XYZ
      SYMMETRY CUBIC
    &END CELL
    &COORD
     ....[I omitted the coors here ]
      SCALED T
    &END COORD
    &KIND Cs
      ELEMENT Cs
      BASIS_SET DZVP-MOLOPT-SR-GTH
      AUX_FIT_BASIS_SET FIT11
      POTENTIAL GTH-PBE-q9
    &END KIND
    &KIND In
      ELEMENT In
      BASIS_SET DZVP-MOLOPT-SR-GTH
      AUX_FIT_BASIS_SET FIT11
      POTENTIAL GTH-PBE-q13
    &END KIND
    &KIND Ag
      ELEMENT Ag
      BASIS_SET DZVP-MOLOPT-SR-GTH
      AUX_FIT_BASIS_SET FIT11
      POTENTIAL GTH-PBE-q11
    &END KIND
    &KIND Cl
      ELEMENT Cl
      BASIS_SET DZVP-MOLOPT-SR-GTH
      AUX_FIT_BASIS_SET FIT3
      POTENTIAL GTH-PBE-q7
    &END KIND
  &END SUBSYS
&END FORCE_EVAL
-----------------------------------------------------------------------------------------------

PBE0 input


--------------------------------------------------------
&GLOBAL
 PROJECT_NAME CsInAgCl
 RUN_TYPE ENERGY
 PRINT_LEVEL LOW
&END GLOBAL
&FORCE_EVAL
 METHOD QS
  &DFT
    BASIS_SET_FILE_NAME BASIS_MOLOPT
    BASIS_SET_FILE_NAME BASIS_ADMM
    BASIS_SET_FILE_NAME BASIS_ADMM_MOLOPT
    POTENTIAL_FILE_NAME GTH_POTENTIALS
    WFN_RESTART_FILE_NAMEPBE.wfn
    &QS
     EPS_PGF_ORB 1.0e-6
    &END
    &MGRID
      CUTOFF 250
      REL_CUTOFF 60
    &END MGRID
    &XC
      &XC_FUNCTIONAL
       &PBE
        SCALE_X 0.75
        SCALE_C 1.0
       &END PBE
       &PBE_HOLE_T_C_LR
        CUTOFF_RADIUS 5.25
        SCALE_X 0.25
       &END PBE_HOLE_T_C_LR
      &END XC_FUNCTIONAL
      &HF
       FRACTION 0.25
       &SCREENING
        EPS_SCHWARZ 1.0e-6
       &END SCREENING
       &INTERACTION_POTENTIAL
        POTENTIAL_TYPE TRUNCATED
        CUTOFF_RADIUS 5.25
        T_C_G_DATA ./t_c_g.dat
       &END INTERACTION_POTENTIAL
       &MEMORY
        MAX_MEMORY 2400
        EPS_STORAGE_SCALING 0.1
       &END MEMORY
      &END HF
    &END XC
    &SCF
      MAX_SCF 100
      EPS_SCF 1.0e-6
      CHOLESKY INVERSE
      SCF_GUESS RESTART
      &OT
       PRECONDITIONER FULL_ALL
       ENERGY_GAP 0.01
      &END OT
    &END SCF
    &AUXILIARY_DENSITY_MATRIX_METHOD
     METHOD BASIS_PROJECTION
     ADMM_PURIFICATION_METHOD MO_DIAG
    &END AUXILIARY_DENSITY_MATRIX_METHOD
    &PRINT
     &MO_CUBES
      WRITE_CUBE F
      NHOMO 1
      NLUMO 1
     &END MO_CUBES
    &END PRINT
  &END DFT
  &SUBSYS
    &CELL
      ABC [angstrom] 10.5345 10.5345 10.5345
      ALPHA_BETA_GAMMA [deg] 90 90 90
      PERIODIC XYZ
      SYMMETRY CUBIC
    &END CELL
    &COORD
       .......
      SCALED T
    &END COORD
    &KIND Cs
      ELEMENT Cs
      BASIS_SET DZVP-MOLOPT-SR-GTH
      AUX_FIT_BASIS_SET FIT11
      POTENTIAL GTH-PBE-q9
    &END KIND
    &KIND In
      ELEMENT In
      BASIS_SET DZVP-MOLOPT-SR-GTH
      AUX_FIT_BASIS_SET FIT11
      POTENTIAL GTH-PBE-q13
    &END KIND
    &KIND Ag
      ELEMENT Ag
      BASIS_SET DZVP-MOLOPT-SR-GTH
      AUX_FIT_BASIS_SET FIT11
      POTENTIAL GTH-PBE-q11
    &END KIND
    &KIND Cl
      ELEMENT Cl
      BASIS_SET DZVP-MOLOPT-SR-GTH
      AUX_FIT_BASIS_SET FIT3
      POTENTIAL GTH-PBE-q7
    &END KIND
  &END SUBSYS
&END FORCE_EVAL

--------------------------------------




Best,

Xiaoming Wang


  
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