# Hybrid functional calculation for C in the diamond structure # in a self-consistent approach # Dataset 1: ground state calculation with WFK output # Dataset 2-6: calculation of five iterations of PBE0-1/3 in the Kohn-Sham basis # Dataset 7: PBE0-1/3 calculation in the planewave basis set # Dataset 8-13: G0W0 calculations, on top of GGA, PBE0-1/3 (Kohn-Sham) and PBE0-1/3 (planewaves). # ndtset 13 gwpara 2 enunit 1 gw_qprange -14 # Compute correction for all the bands #gw_qprange -30 # Compute correction for all the bands prtvol 2 symsigma 0 # Dataset1: usual self-consistent ground-state calculation # Definition of the k-point grid ngkpt 2 2 2 nshiftk 4 shiftk 0.0 0.0 0.0 # This grid contains the Gamma point 0.0 0.5 0.5 0.5 0.0 0.5 0.5 0.5 0.0 tolvrs 1.0d-15 nband 14 #nband 30 istwfk *1 # Option needed for Gamma getwfk1 0 # Common to most hybrid/GW calculations getwfk 1 # Obtain WFK file from dataset 1 ecutwfn 8 # Planewaves to be used to represent the wavefunctions #ecutwfn 20 # Planewaves to be used to represent the wavefunctions ecutsigx 8 # Planewaves to be used to represent the exchange operator #ecutsigx 40 # Planewaves to be used to represent the exchange operator ecuteps 2 gwcalctyp 25 getqps -1 ixc_sigma 42 pawecutdg 40 # Dataset2: Calculation of the 1st PBE0-1/3 iteration optdriver2 4 gw_icutcoul2 0 # Will use the spherical average rcut2 -1.0d0 # A negative number actually activates the computation of rcut using the Spencer-Alavi value # Dataset3: Calculation of the 2nd PBE0-1/3 iteration optdriver3 4 getqps3 -1 gw_icutcoul3 0 # Will use the spherical average rcut3 -1.0d0 # A negative number actually activates the computation of rcut using the Spencer-Alavi value # Dataset4: Calculation of the 3rd PBE0-1/3 iteration optdriver4 4 getqps4 -1 gw_icutcoul4 0 # Will use the spherical average rcut4 -1.0d0 # A negative number actually activates the computation of rcut using the Spencer-Alavi value # Dataset5: Calculation of the 4th PBE0-1/3 iteration optdriver5 4 getqps5 -1 gw_icutcoul5 0 # Will use the spherical average rcut5 -1.0d0 # A negative number actually activates the computation of rcut using the Spencer-Alavi value # Dataset6: Calculation of the 5th PBE0-1/3 iteration optdriver6 4 getqps6 -1 gw_icutcoul6 0 # Will use the spherical average rcut6 -1.0d0 # A negative number actually activates the computation of rcut using the Spencer-Alavi value # Dataset7: PBE0-1/3 stand alone calculation getwfk7 1 ixc7 42 # Dataset8: Computation of the dielectric matrix on top of scGGA in the PW basis optdriver8 3 gwcalctyp8 0 # Dataset9: One-shot G0W0 on top of scGGA in the Kohn-Sham basis optdriver9 4 gwcalctyp9 0 getscr9 -1 gw_qprange9 0 gw_icutcoul9 0 # Will use the spherical average rcut9 -1.0d0 # A negative number actually activates the computation of rcut using the Spencer-Alavi value # Dataset10: Computation of the dielectric matrix on top of scPBE0-1/3 in the Kohn-Sham basis optdriver10 3 gwcalctyp10 20 getqps10 6 # Dataset11: One-shot G0W0 on top of scPBE0-1/3 in the Kohn-Sham basis # (note however that all the bands and k points are considered, in orer to perform the correct rotation). optdriver11 4 gwcalctyp11 20 getqps11 6 getscr11 -1 gw_icutcoul11 0 # Will use the spherical average rcut11 -1.0d0 # A negative number actually activates the computation of rcut using the Spencer-Alavi value # Dataset12: Computation of the dielectric matrix on top of scPBE0-1/3 in the planewave basis optdriver12 3 getwfk12 7 gwcalctyp12 20 getqps12 0 # Dataset13: One-shot G0W0 on top of scPBE0-1/3 in the planewave basis optdriver13 4 ixc13 42 #One should not forget to mention than the starting functional is NOT the one of the pseudopotential ... getwfk13 7 gwcalctyp13 0 getqps13 0 getscr13 -1 gw_qprange13 0 gw_icutcoul13 0 # Will use the spherical average rcut13 -1.0d0 # A negative number actually activates the computation of rcut using the Spencer-Alavi value # Definition of the unit cell: fcc acell 3*6.7406530878521345 #Same parameters as Shiskin rprim 0.0 0.5 0.5 #FCC primitive vectors (to be scaled by acell) 0.5 0.0 0.5 0.5 0.5 0.0 # Definition of the atom types ntypat 1 znucl 6 # Definition of the atoms natom 2 # There are two atoms typat 1 1 xred # Reduced coordinate of atoms 0.0 0.0 0.0 0.25 0.25 0.25 # Definition of the planewave basis set (at convergence 16 Rydberg 8 Hartree) ecut 8 # Maximal kinetic energy cut-off, in Hartree # ecut 20 # Maximal kinetic energy cut-off, in Hartree # Definition of the SCF procedure nstep 250 # Maximal number of SCF cycles diemac 12.0 # Although this is not mandatory, it is worth to # precondition the SCF cycle. The model dielectric # function used as the standard preconditioner # is described in the "dielng" input variable section. # Here, we follow the prescription for bulk silicon. pp_dirpath "$ABI_PSPDIR" pseudos "C.psp8" #%% #%% [setup] #%% executable = abinit #%% [files] #%% files_to_test = #%% t68.out, tolnlines=67, tolabs= 4.0e-3, tolrel= 1.0e-1, fld_options = -easy #%% [paral_info] #%% max_nprocs = 6 #%% [extra_info] #%% authors = F. Bruneval and X. Gonze #%% keywords = GW #%% description = #%% Diamond: G0W0 @ scPBE0-1/3 calculation. Monitor the direct gap at Gamma. #%% #%% First, with the scGW methodology based on a Kohn-Sham basis, #%% then doing the scPBE0 using the planewave basis, followed by a one-shot G0W0. #%% The agreement is reasonable with the parameters used in the automatic test, #%% but can be improved with better parameters (esp. nband), see later. #%% At the PBE level, the (KS) band gap is 5.231 eV, #%% At the scPBE0-1/3 level, the Kohn-Sham basis delivers 8.101 eV, #%% while the plane wave basis delivers 8.122 eV. #%% At the G0W0-scPBE0-1/3 level, the Kohn-Sham basis delivers 7.638 eV, #%% while the plane wave basis delivers 7.659 eV. #%% The macroscopic dielectric constant (at Gamma) is 9.3698 from PBE, #%% 4.4126 from scPBE0-1/3(KS) and 4.4105 from scPBE0-1/3(planewaves). #%% #%% These calculations have also been done with better #%% parameters, in order to observe a better agreement between the KS basis set and the #%% planewave basis set (ecut 20 ecutsigx 20 nband 30 gw_qprange 30 - note however that ecuteps 2 is low), #%% at the expense of CPU time.. #%% In this case, one used the PBE0 functional (ixc_sigma=41 or ixc_sigma=-406, #%% of even isc_sigma=42 with hyb_mixing=0.25 - all the cases were checked). #%% At the PBE level, the (KS) band gap was 5.661 eV, #%% At the scPBE0 level, the Kohn-Sham basis delivered 7.882 eV, #%% while the plane wave basis delivered 7.884 eV. #%% At the G0W0-scPBE0 level, the Kohn-Sham basis delivered 7.820 eV, #%% while the plane wave basis delivered 7.827 eV. #%% The macroscopic dielectric constant (at Gamma) was 7.845 from PBE, #%% 4.483 from scPBE0(KS) and 4.490 from scPBE0(planewaves). #%%