#AlAs in hypothetical wurzite (hexagonal) structure
#Structural optimization run
ndtset 2 # There are 2 datasets in this calculation
# Set 1 : Internal coordinate optimization
ionmov1 2 # Use BFGS algorithm for structural optimization
ntime1 5 # Maximum number of optimization steps
tolmxf1 1.0e-6 # Optimization is converged when maximum force
# (Hartree/Bohr) is less than this maximum
natfix1 2 # Fix the position of two symmetry-equivalent atoms
# in doing the structural optimization
iatfix1 1 2 # Choose atoms 1 and 2 as the fixed atoms (see discussion)
# Set 2 : Lattice parameter relaxation (including re-optimization of
# internal coordinates)
dilatmx2 1.05 # Maximum scaling allowed for lattice parameters
getxred2 -1 # Start with relaxed coordinates from dataset 1
getwfk2 -1 # Start with wave functions from dataset 1
ionmov2 2 # Use BFGS algorithm
ntime2 12 # Maximum number of optimization steps
optcell2 2 # Fully optimize unit cell geometry, keeping symmetry
tolmxf2 1.0e-6 # Convergence limit for forces as above
strfact2 100 # Test convergence of stresses (Hartree/bohr^3) by
# multiplying by this factor and applying force
# convergence test
natfix2 2
iatfix2 1 2
#Common input data
#Starting approximation for the unit cell
acell 7.5 7.5 12.263388 #this is a guess, with the c/a
#ratio based on ideal tetrahedral
#bond angles
rprim 0.866025403784439 0.5 0.0 #hexagonal primitive vectors must be
-0.866025403784439 0.5 0.0 #specified with high accuracy to be
0.0 0.0 1.0 #sure that the symmetry is recognized
#and preserved in the optimization
#process
#Definition of the atom types and atoms
ntypat 2
znucl 13 33
natom 4
typat 1 1 2 2
#Starting approximation for atomic positions in REDUCED coordinates
#based on ideal tetrahedral bond angles
xred 1/3 2/3 0.0
2/3 1/3 0.5
1/3 2/3 0.375
2/3 1/3 0.875
#Gives the number of bands, explicitely (do not take the default)
nband 8 # For an insulator (if described correctly as an
# insulator by DFT), conduction bands should not
# be included in response-function calculations
#Definition of the plane wave basis set
ecut 6.0 # Maximum kinetic energy cutoff (Hartree)
ecutsm 0.5 # Smoothing energy needed for lattice paramete
# optimization. This will be retained for
# consistency throughout.
#Definition of the k-point grid
ngkpt 4 4 4 # 4x4x4 Monkhorst-Pack grid
nshiftk 1 # Use one copy of grid only (default)
shiftk 0.0 0.0 0.5 # This choice of origin for the k point grid
# preserves the hexagonal symmetry of the grid,
# which would be broken by the default choice.
#Definition of the self-consistency procedure
diemac 9.0 # Model dielectric preconditioner
nstep 40 # Maxiumum number of SCF iterations
tolvrs 1.0d-18 # Strict tolerance on (squared) residual of the
# SCF potential needed for accurate forces and
# stresses in the structural optimization, and
# accurate wave functions in the RF calculations
# enforce calculation of forces at each SCF step
optforces 1
## After modifying the following section, one might need to regenerate the pickle database with runtests.py -r
#%%
#%% [setup]
#%% executable = abinit
#%% [files]
#%% files_to_test =
#%% telast_1.out, tolnlines= 0, tolabs= 0.000e+00, tolrel= 0.000e+00
#%% psp_files = 13al.pspnc, 33as.pspnc
#%% [paral_info]
#%% max_nprocs = 2
#%% [extra_info]
#%% authors = D. Hamann
#%% keywords =
#%% description =
#%% AlAs in hypothetical wurzite (hexagonal) structure
#%% Structural optimization run
#%%