# Ytterbium, one atom per primitive cell, fcc structure
# test of ddk for l=3, compute derivative of eigenenergy
# Warning : completely unphysical, as yb is treated as an insulator
# with a crazy cut-off, and only 2 k points

 ndtset 3

#For most datasets
 nkpt 2
 kpt 3*0.25
     0.25 0.5 0.5
 wtk 1 3

#Dataset 1
 prtden1 1
 tolwfr1 1.0d-21
 nstep1  30

#Dataset 2
 getden2 1
 iscf2 -2
 nkpt2  3
 nstep2 15
 kpt2   0.2500 0.2500 0.2500
        0.251  0.251  0.251
        0.253  0.253  0.253

#Dataset 3
 rfelfd3 2
 rfdir3  1 0 0
 getwfk3 1
 getddk3 3   ! This is needed for the localisation tensor
 nstep3  1
 iscf3  -3


#Common data
 acell 3*10.000
 dielng 0.8
 ecut 4.5
 enunit 2
  kptopt 0
 natom  1
 nband 10
 occopt 7
 tolwfr 1.0d-14
 typat  1
 xred 3*0.00d0
 znucl  70.0

 pp_dirpath "$ABI_PSPDIR"
 pseudos "PseudosTM_pwteter/70yb.pspnc"

#%%<BEGIN TEST_INFO>
#%% [setup]
#%% executable = abinit
#%% [files]
#%% files_to_test = 
#%%   t09.out, tolnlines = 0, tolabs = 0.000e+00, tolrel = 0.000e+00, fld_options = -easy
#%% [paral_info]
#%% max_nprocs = 2
#%% [extra_info]
#%% authors = Unknown
#%% keywords = NC, DFPT
#%% description = 
#%%     FCC Yb (1 atom per unit cell),
#%%     using a l=3 psp with s local part.
#%%     Crazy cut-off and number of k points.
#%%     Shows that the derivative of the eigenenergies
#%%     with respect to the wavevector can be obtained
#%%     both by finite differences and analytical means
#%%     (from a preliminary computation in the
#%%     treatment of the ddk perturbation).
#%%     For the (0.25,0.25,0.25) k point,
#%%     the tenth band eigenvalue is -3.01209 eV.
#%%     Going to the (0.251,0.251,0.251) k point
#%%     it becomes -3.00562 eV, with finite-difference
#%%     estimation of the derivative with respect
#%%     to ONE wavevector change (all three
#%%     components changed) being 0.00647 eV/0.001/3=2.157 eV
#%%     This value is unchanged when using the
#%%     data at the (0.253,0.253,0.253) k point.
#%%     The analytical value is 2.15566 eV.
#%%<END TEST_INFO>