#AlAs in hypothetical wurzite (hexagonal) structure
#Response function calculation for:
# * rigid-atom elastic tensor
# * rigid-atom piezoelectric tensor
# * interatomic force constants at gamma
# * Born effective charges
ndtset 3
# Set 1 : Initial self-consistent run
kptopt1 1
tolvrs1 1.0d-18 #need excellent convergence of GS quantities for RF runs
# Set 2 : Calculate the ddk wf's - needed for piezoelectric tensor and
# Born effective charges in dataset 3
getwfk2 -1
iscf2 -3 #this option is needed for ddk
kptopt2 2 #use time-reversal symmetry only for k points
nqpt2 1 #one wave vector will be specified
qpt2 0 0 0 #need to specify gamma point
rfelfd2 2 #set for ddk wf's only
rfdir2 1 1 1 #full set of directions needed
tolwfr2 1.0d-20 #only wf convergence can be monitored here
# Set 3 : response-function calculations for all needed perturbations
getddk3 -1
getwfk3 -2
kptopt3 2 #use time-reversal symmetry only for k points
nqpt3 1
qpt3 0 0 0
rfphon3 1 #do atomic displacement perturbation
rfatpol3 1 4 #do for all atoms
rfstrs3 3 #do strain perturbation
rfdir3 1 1 1 #the full set of directions is needed
tolvrs3 1.0d-10 #need reasonable convergence of 1st-order quantities
#Common input data
# acell COPY RELAXED RESULT FROM PREVIOUS CALCULATION
# Here is a default value, for automatic testing : suppress it and fill the previous line
acell 7.5389648144E+00 7.5389648144E+00 1.2277795374E+01
rprim sqrt(0.75) 0.5 0.0 #hexagonal primitive vectors must be
-sqrt(0.75) 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 COPY RELAXED RESULT FROM PREVIOUS CALCULATION
# Here is a set of default values, for automatic testing : suppress it and fill the previous line
xred 1/3 2/3 0
2/3 1/3 1/2
1/3 2/3 3.7608588373E-01
2/3 1/3 8.7608588373E-01
#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
kptopt 1 # Use symmetry and treat only inequivalent points
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
# enforce calculation of forces at each SCF step
optforces 1
#%%
#%% [setup]
#%% executable = abinit
#%% test_chain = telast_2.in, telast_3.in
#%% [files]
#%% files_to_test =
#%% telast_2.out, tolnlines= 0, tolabs= 0.000e+00, tolrel= 0.000e+00, fld_options = -easy
#%% psp_files = 13al.pspnc, 33as.pspnc
#%% [paral_info]
#%% max_nprocs = 2
#%% [extra_info]
#%% authors = D. Hamann
#%% keywords = NC, DFPT
#%% description =
#%% AlAs in hypothetical wurzite (hexagonal) structure
#%% Response function calculation for:
#%% * rigid-atom elastic tensor
#%% * rigid-atom piezoelectric tensor
#%% * interatomic force constants at gamma
#%% * Born effective charges
#%%