# Crystalline Cu2O : computation of the total energy
# and EFG tensors in DFT+U formalism
# Note: Cu2O is a nonmagnetic insulator
#

#Specific to ground state calculation


usepawu 1 # DFT+U with PAW data
lpawu 2 -1 # d electrons of copper treated with DFT+U, oxygen not treated
upawu 0.30 0.0 # U for copper is 0.30 Ha
jpawu 0.03 0.0 # J for copper is 0.03 Ha
dmatpuopt  1   # choose expression of the density matrix
nspden 2 # must use nspden = 2 for DFT+U currently
nsppol 2    spinmagntarget 0.0d0
ixc 1 # PAW data was made with ixc = 2 but have to change to ixc 1 for DFT+U


ecut 10 # use 20 for converged answer
pawecutdg 30 # use 50 for converged answer
pawmixdg 1
toldfe 1.0D-8
prtwf 0
prtden 0
prteig 0

prtefg 2 # get full report of efg tensors
quadmom 0.22 -0.0261 # quad moment for copper and oxygen

#######################################################################
#Common input variables


#Definition of the unit cell
acell 3*4.2676 angstrom # experimental structure of Cu2O
#kspace
ngkpt 2 2 2 # use ngkpt 6 6 6 for converged answer

#Definition of the atom types
ntypat 2               # There are two types of atom
znucl 29 8            # The keyword "znucl" refers to the atomic number of the
                       # possible type(s) of atom. The pseudopotential(s)
                       # mentioned in the "files" file must correspond
                       # to the type(s) of atom.

#Definition of the atoms
natom  6
natrd  6
typat 2*2 4*1 # Cu O

xred                     # This keyword indicate that the location of the atoms
0.0 0.0 0.0
0.5 0.5 0.5
0.25 0.25 0.25
0.25 -0.25 -0.25
-0.25 0.25 -0.25
-0.25 -0.25 0.25

# band information
occopt 1
#Definition of the SCF procedure
nstep 50               # Maximal number of SCF cycles

 pp_dirpath "$ABI_PSPDIR"
 pseudos "cu_ps.736.lda, o_ps.736.lda"

#%%<BEGIN TEST_INFO>
#%% [setup]
#%% executable = abinit
#%% [files]
#%% files_to_test = 
#%%   t33.out, tolnlines = 2, tolabs = 1.100e-05, tolrel = 5.000e-06, fld_options = -medium
#%% [paral_info]
#%% max_nprocs = 2
#%% [extra_info]
#%% authors = Unknown
#%% keywords = PAW, DFTU
#%% description = 
#%%   Crystalline Cu2O
#%%   Computation of the total energy and EFG tensors in DFT+U formalism
#%%   Note: Cu2O is a nonmagnetic insulator. However, DFT+U
#%%   as implemented requires nspden=2 in all cases.
#%% topics = DFT+U, EFG
#%%<END TEST_INFO>