# Input for Positron tutorial # Sixth step (part 2) of the tutorial on electron-positron annihilation # Doppler spectrum calculation within PAW - 12 valence electrons # Si, 2 atoms in the box # This input file is similar to tpositron_5.abi, except: # - the number of bands, because of the additional 8 electrons states # - the plane wave cut-off energy because additional PAW basis functions are localized #------------------------------------------------------------------------------- #Definition of variables specific to electron-positron calculation #TC-DFT Self-consistent cycle positron -10 # We perform automatic calculation of electrons and positron densities # in the two-component DFT context (storing wavefunctions in memory) # Automatic electron-positron loop has to be switched on in Doppler calculations # to have both electron and positron wavefunctions in memory posnstep 2 # Maximum number of electon and positron steps = 2 # We simulate a delocalized positron, so we only perform two steps # of electon-positron calculations. It means that the electronic # wavefunction is not affected by the positron. posdoppler 1 # Activation of Doppler broadening calculation ixcpositron 1 # We are using the Boronski and Nieminen parametrization posocc 1.0 # Occupation number for the positron # (should be set <1 for bulk calculation with a small cell). # Here the zero positron density limit is used, # so results do not depend on posocc. # Note about Brillouin zone sampling: # In Doppler calculation we need to have a uniform k-point grid # in the momentum space. Symmetries are not used, # so the full grid needs to be specified. # so results do not depend on posocc. #------------------------------------------------------------------------------- #Definition of data common to all datasets #Definition of the unit cell acell 3*5.43 angstrom # Lengths of the primitive vectors (exp. param. in angstrom) rprim # 3 orthogonal primitive vectors (FCC lattice) 0.0 1/2 1/2 1/2 0.0 1/2 1/2 1/2 0.0 #Definition of the atom types and pseudopotentials ntypat 1 # There is only one type of atom znucl 14 # Atomic number of the possible type(s) of atom. Here silicon. pp_dirpath "$ABI_PSPDIR" # Path to the directory were # pseudopotentials for tests are stored pseudos "Si_paw_pw_12el.xml" # Name and location of the pseudopotential #Definition of the atoms natom 2 # There are two atoms typat 1 1 # They both are of type 1, that is, Silicon xred # Location of the atoms: 0.0 0.0 0.0 # Triplet giving the reduced coordinates of atom 1 1/4 1/4 1/4 # Triplet giving the reduced coordinates of atom 2 #Definition of bands and occupation numbers nband 16 # Compute 16 bands (we have semicore states) occopt 1 # Automatic generation of occupation numbers, as a semiconductor #Numerical parameters of the calculation : planewave basis set and k point grid ecut 12. # Maximal plane-wave kinetic energy cut-off, in Hartree pawecutdg 15. # Max. plane-wave kinetic energy cut-off, in Ha, for the PAW double grid # In Doppler broadening calculation we need to have a uniform # k-point grid in the momentum space. Symmetries are not used, # so the full grid needs to be specified. kptopt 0 # - Option for manual setting of k-points istwfk *1 # - No time-reversal symmetry optimization nkpt 8 # - Corresponds to a 2x2x2 grid, denser grids may be needed to get converged spectra kpt # - K-point coordinates in reciprocal space: 0 0 0 0 0 0.5 0 0.5 0 0.5 0 0 0 0.5 0.5 0.5 0 0.5 0.5 0.5 0 0.5 0.5 0.5 #Parameters for the SCF procedure nstep 100 # Maximal number of SCF cycles tolvrs 1.0d-10 # Will stop when, twice in a row, the difference # between two consecutive evaluations of potential residual # differ by less than tolvrs # We need additional parameters to imporve the convergency: nline 8 # - increase the number of iterations of the minimization algorithm nnsclo 2 # - perform 2 non-self-consistent loop per SCF cycle nbdbuf 16 # This is to make the test portable (don't use this usually) #Miscelaneous parameters prtwf 0 # Do not print wavefunctions prtden 1 # Print density (electronic and/or positronic) prteig 0 # Do not print eigenvalues optforces 0 # Forces computation is not relevant here optstress 0 # Stress tensor computation is not relevant here ############################################################## # This section is used only for regression testing of ABINIT # ############################################################## #%% #%% [setup] #%% executable = abinit #%% [files] #%% files_to_test = #%% tpositron_7.abo, tolnlines= 7, tolabs=9., tolrel= 1.0, fld_options= -easy #%% [paral_info] #%% max_nprocs = 10 #%% [extra_info] #%% authors = J. Wiktor #%% keywords = POSITRON,PAW #%% description = #%% Input for Positron tutorial #%% Sixth step (part 2) of the tutorial on electron-positron annihilation #%% Doppler spectrum calculation within PAW - 12 valence electrons #%% Si, 2 atoms in the box #%%