# Finite difference calculation of the clamped-ion
# piezoelectric constants of AlAs
# (M. Veithen, 3.5.2005)

ndtset 3

# strain: eta_4 = 0.00
acell1     3*7.44856
rprim1        0.0000000000E+00  7.0710678119E-01  7.0710678119E-01
              7.0710678119E-01  0.0000000000E+00  7.0710678119E-01
              7.0710678119E-01  7.0710678119E-01  0.0000000000E+00 

# strain: eta_4 = 0.01
acell2  7.4858028  2*7.44856
rprim2     0.                     0.70710678118654746    0.70710678118654746 
           0.70710236181059671    0.00353551180905298    0.70710236181059671 
           0.70710236181059671    0.70710236181059671    0.00353551180905298

# strain: eta_4 = -0.01     2*7.44856
acell3  7.4113172  2*7.44856
rprim3     0.                     0.70710678118654757    0.70710678118654757
           0.70710236181059671   -0.00353551180905298    0.70710236181059671 
           0.70710236181059671    0.70710236181059671   -0.00353551180905298

tolsym 1.0e-8 # Since we make rather small lattice vector changes, with the default value of tolsym
              # ABINIT will recognize that we are close to a more symmetric
              # configuration, and will resymmetrize the primitive vectors, something we want to avoid ...


#Definition of the atoms
#***********************
   natom 2
   ntypat 2
   znucl 13 33
   typat 1 2
   ixc 3
   xred   0.00  0.00  0.00
          0.25  0.25  0.25

#Definition of the SCF procedure
#*******************************
   nstep 100


#Definition of the plane wave basis set
#**************************************
   ecut  2.8
   ecutsm 0.5
   dilatmx 1.05
   ngkpt 6 6 6
   nshiftk 4
   shiftk 0.5 0.5 0.5
          0.5 0.0 0.0
          0.0 0.5 0.0
          0.0 0.0 0.5
   toldfe 1.0d-12

# Berry phase calculation of the polarization
#********************************************
   berryopt -1
   rfdir 1 1 1



 pp_dirpath "$ABI_PSPDIR"
 pseudos "PseudosTM_pwteter/13al.pspnc, PseudosTM_pwteter/33as.pspnc"

#%%<BEGIN TEST_INFO>
#%% [setup]
#%% executable = abinit
#%% [files]
#%% files_to_test = 
#%%   tffield_4.out, tolnlines=  3, tolabs= 9.999e-9, tolrel= 1.224e-04
#%% [paral_info]
#%% max_nprocs = 2
#%% [extra_info]
#%% authors = M. Veithen
#%% keywords = NC, DFPT
#%% description = 
#%%  Finite difference calculation of the clamped-ion
#%%  piezoelectric constants of AlAs
#%%<END TEST_INFO>