&GLOBAL PROJECT anatase_25hfx ! Project name, remember to change it for each calculation RUN_TYPE ENERGY &END GLOBAL &FORCE_EVAL METHOD Quickstep &DFT ! external data-files for basis-set, pseudo-potentials and wave-function to restart from BASIS_SET_FILE_NAME ./BASIS_TiO POTENTIAL_FILE_NAME ./POTENTIALS_TiO RESTART_FILE_NAME ./pbe-RESTART.wfn &MGRID ! section required to define the cutoff of the grids in the program CUTOFF 400 ! for this system the default value is too small &END MGRID ! and can lead to non-physical results &PRINT ! section required to obtain the HOMO-LUMO gap. &MO_CUBES WRITE_CUBE .FALSE. ! no cube file is generated NHOMO 1 ! but we require 1 HOMO and 1 LUMO in the output NLUMO 1 ! so that we get the band gap &END &END &SCF ! ensures convergence of the SCF cycle EPS_SCF 1.0E-6 SCF_GUESS RESTART ! here we specify to restart from an external wave-function (name specified above) MAX_SCF 40 &OUTER_SCF EPS_SCF 1.0E-6 MAX_SCF 10 &END &OT PRECONDITIONER FULL_ALL ENERGY_GAP 0.01 &END OT &END SCF &XC ! this is the section to define the electronic exchange &XC_FUNCTIONAL ! our functional is hybrid &PBE ! it has 75% of PBE SCALE_X 0.75 SCALE_C 1.0 &END &PBE_HOLE_T_C_LR SCALE_X 0.25 ! + 25% of truncated PBE0 functional - that includes exact hfx CUTOFF_RADIUS 3.5 ! that has interaction truncated at 3.5 A from the atomic core &END &END XC_FUNCTIONAL &HF FRACTION 0.25 ! this is the hfx section. The amount of hfx must be consistent with above &SCREENING ! Screening of the electronic repulsion up to the given threshold. This section is needed EPS_SCHWARZ 1.0E-6 SCREEN_ON_INITIAL_P TRUE ! having an external wave-function, a preliminary screening &END ! can be performed to speed up calculations &MEMORY MAX_MEMORY 800 ! uses some memory to store data and not recompute each step &END &INTERACTION_POTENTIAL ! Sets up interaction potential between the two regions POTENTIAL_TYPE TRUNCATED ! the potential is truncated CUTOFF_RADIUS 3.5 ! at 3.5 A (see above) T_C_G_DATA ./t_c_g.dat ! external file with parameters needed to truncate the potential &END &END &END &END DFT &SUBSYS &CELL ABC 3.7842 3.7842 9.5146 ! anatase crystal unit cell MULTIPLE_UNIT_CELL 2 2 1 ! a 2x2x1 system is required to get realistic results &END CELL &TOPOLOGY MULTIPLE_UNIT_CELL 2 2 1 ! a 2x2x1 system is required to get realistic results. This has to be repeated here. COORD_FILE_FORMAT CIF ! specifies the type and name of coordinate file COORD_FILE_NAME tio.cif &END &KIND O ! external basis and pseudo-potentials for Ti and O BASIS_SET cpFIT3 POTENTIAL GTH-PBE-q6 &END KIND &KIND Ti BASIS_SET FIT POTENTIAL GTH-PBE-q12 &END KIND &END SUBSYS &END FORCE_EVAL