# H2 molecule in a big box
#
# This file to optimize the H2 bond length, compute the associated total
# energy, then to compute the total energy of the isolated H atom.
# Here, a double loop has been used.
#
ndtset 12 udtset 6 2
#Definition of the unit cell and ecut,
#for which one will have to make a convergence study
acell 10 10 10
ecut:? 10 ecut+? 5
#First dataset : find the optimal bond length of H2, and associated total energy
natom?1 2 # There are two atoms
ionmov?1 2 # Use the modified Broyden algorithm
ntime?1 10 # Maximum number of Broyden "timesteps"
tolmxf?1 5.0d-4 # Stopping criterion for the geometry optimization : when
# the residual forces are less than tolmxf, the Broyden
# algorithm can stop
xcart?1 -0.7 0.0 0.0 # The starting values of the
0.7 0.0 0.0 # atomic coordinates
toldff?1 5.0d-5 # Will stop the SCF cycle when, twice in a row,
# the difference between two consecutive evaluations of
# forces differ by less than toldff (in Hartree/Bohr)
nband?1 1 # Just one band
#Second dataset : get the total energy of the isolated atom
natom?2 1 # There is one atom
nsppol?2 2 # Spin-polarized calculation
occopt?2 2 # Allow occupation numbers to be set by hand
nband?2 1 1 # Number of bands for spin up and spin down
occ?2 1.0 0.0 # Occupation numbers for spin up state and spin down state.
toldfe?2 1.0d-6 # Will stop the SCF cycles when, twice in a row,
# the difference between two consecutive evaluations
# of total energy differ by less than toldfe (in Hartree)
# This value is way too large for most realistic studies of materials
xcart?2 0.0 0.0 0.0 # The atom is located at the origin
spinat?2 0.0 0.0 1.0 # Initialisation of spin
#rprim 1 0 0 0 1 0 0 0 1 # This line, defining orthogonal primitive vectors,
# is commented, because it is precisely the default value of rprim
#Definition of the atom types
ntypat 1 # There is only one type of atom
znucl 1 # The keyword "znucl" refers to the atomic number of the possible type(s) of atom.
# Here, the only type is Hydrogen. The pseudopotential(s)
# mentioned after the keyword "pseudos" should correspond to this type of atom.
pp_dirpath "$ABI_PSPDIR" # This is the path to the directory were pseudopotentials for tests are stored
pseudos "Pseudodojo_nc_sr_04_pw_standard_psp8/H.psp8" # Name and location of the pseudopotential
# This pseudopotential comes from the pseudodojo site http://www.pseudo-dojo.org/ (NC SR LDA standard),
# and was generated using the LDA exchange-correlation functional (PW=Perdew-Wang, ixc=-1012).
# By default, abinit uses the same exchange-correlation functional than the one of the input pseudopotential(s)
#Definition of the atoms
typat 1 1 # For the first dataset, both numbers will be read,
# while for the second dataset, only one number will be read
#Definition of the k-point grid
kptopt 0 # Enter the k points manually
nkpt 1 # Only one k point is needed for isolated system,
# taken by default to be 0.0 0.0 0.0
#Definition of the SCF procedure
nstep 10 # Maximal number of SCF cycles
#toldfe is no more defined, as toldff is used above...
diemac 2.0 # 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 prescriptions for molecules
# in a big box
##############################################################
# This section is used only for regression testing of ABINIT #
##############################################################
#%%
#%% [setup]
#%% executable = abinit
#%% [files]
#%% files_to_test =
#%% tbase2_2.abo, tolnlines= 0, tolabs= 0.000e+00, tolrel= 0.000e+00, fld_options=-medium
#%% [paral_info]
#%% max_nprocs = 1
#%% [extra_info]
#%% authors = X. Gonze
#%% keywords =
#%% description =
#%% H2 molecule in a big box
#%% This file to optimize the H2 bond length, compute the associated total
#%% energy, then to compute the total energy of the isolated H atom.
#%% Here, a double loop has been used.
#%%