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[<gaotaoscu@hotmail.com>]

Dear All,

I get some contradictory suggestions from the phonon calculation error
displayed in ABINIT. On the one hand, my oxide compund(insulator) request the
'occopt 1', otherwise there will have no LO-TO splitting. However, when the
'occopt 1' option were filled in the input file, the calculation error will
suggest you to 'change occopt, consistently, in GS and RF calculations'. Will
you have any suggestion on this problem? Thank you very much in advance.

Best,

Tao

PS, here is my input file. and error displayed.
1) input file,
# Crystalline : computation of the phonon spectrum
   ndtset   10
#Set 1 : ground state self-consistency

  getwfk1   0            # Cancel default
  kptopt1   1            # Automatic generation of k points, taking
  nqpt1   0            # Cancel default
  tolvrs1   1.0d-18      # SCF stopping criterion (modify default)
  rfphon1   0            # Cancel default
 
#Q vectors for all datasets

     nqpt   1            # One qpt for each dataset (only 0 or 1 allowed)
 
     qpt2        0.00000000E+00  0.00000000E+00  0.00000000E+00
     qpt3        0.00000000E+00  0.00000000E+00  0.00000000E+00
     qpt4        2.50000000E-01  0.00000000E+00  0.00000000E+00
     qpt5        5.00000000E-01  0.00000000E+00  0.00000000E+00
     qpt6        2.50000000E-01  2.50000000E-01  0.00000000E+00
     qpt7        5.00000000E-01  2.50000000E-01  0.00000000E+00
     qpt8        -2.50000000E-01  2.50000000E-01  0.00000000E+00
     qpt9        5.00000000E-01  5.00000000E-01  0.00000000E+00
     qpt10       -2.50000000E-01  5.00000000E-01  2.50000000E-01

#Set 2 : Response function calculation of d/dk wave function 

  iscf2   -3         # Need this non-self-consistent option for d/dk
  kptopt2   2          # Modify default to use time-reversal symmetry
  rfphon2   0          # Cancel default
  rfelfd2   2          # Calculate d/dk wave function only
  tolvrs2   0.0        # Cancel default for d/dk
  tolwfr2   1.0d-22    # Use wave function residual criterion instead

#Set 3 : Response function calculation of Q=0 phonons and electric field pert.

  getddk3   2          # d/dk wave functions from last dataset
  kptopt3   2          # Modify default to use time-reversal symmetry
  rfelfd3   3          # Electric-field perturbation response only

#Sets 4-10 : Finite-wave-vector phonon calculations (defaults for all 
datasets)

   getwfk   1          # Use GS wave functions from dataset1
   kptopt   3          # Need full k-point set for finite-Q response
   rfphon   1          # Do phonon response
   rfatpol   1 3        # Treat displacements of all atoms
   rfdir   1 1 1      # Do all directions (symmetry will be used)
   tolvrs   1.0d-8     # This default is active for sets 3-10

#Common input variables
    acell   3*10.349007457  Bohr         # This is equivalent to   10.61 10.61
10.61
    rprim  0.0  0.5  0.5   # In lessons 1 and 2, these primitive vectors 
           0.5  0.0  0.5   # (to be scaled by acell) were 1 0 0  0 1 0  0 0 1 
           0.5  0.5  0.0   # that is, the default.

#Definition of the atom types
   ntypat 2         # There is tow type of atom
   znucl ---   ---      # The keyword "znucl" refers to the atomic number of
the 
  
#Definition of the atoms
   natom 3           # There are two atoms
   typat 1 2 2         # They both are of type 1, that is, Silicon.
   xred              # This keyword indicate that the location of the atoms
                  # will follow, one triplet of number for each atom
   0.0  0.0  0.0  # Triplet giving the REDUCED coordinate of atom 1.
   1/4  1/4  1/4  # Triplet giving the REDUCED coordinate of atom 2.
   3/4  3/4  3/4              # Note the use of fractions (remember the 
limited

  
#Gives the number of band, explicitely (do not take the default)
    nband   12
    occopt 1
#Exchange-correlation functional

      ixc   11             # LDA Teter Pade parametrization

#Definition of the planewave basis set

     ecut   28.0
#Definition of the k-point grid
    ngkpt   4  4  4          
    nshiftk   4              # Use one copy of grid only (default)
    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
  
#Definition of the SCF procedure
     iscf   7          # Self-consistent calculation, using algorithm 5
     nline  15
    nstep   1000         # Maximal number of SCF cycles
   diemac   12.0        # Although this is not mandatory, it is worth to
                       # precondition the SCF cycle. The model dielectric

2) error displayed,

     iter   2DEtotal(Ha)        deltaE(Ha) residm    vres2
 scfcv3, nstep=        1000

 getcut: wavevector=  0.0000  0.0000  0.0000  ngfft=  36  36  36
         ecut(hartree)=     28.000   => boxcut(ratio)=   2.06526
 scfcv3, nstep=        1000
-P-0000  occeig : ERROR -
-P-0000   In a non-metallic case (occopt<3), for a RF calculation,
-P-0000   if the eigenvalues are degenerate, the occupation numbers must also
be degenerate.
-P-0000   However, the following pair of states gave :
-P-0000   k -state, band number   9, occ=    2.000000E+00, eigenvalue=  
-2.507767E-01,
-P-0000   kq-state, band number  10, occ=    0.000000E+00, eigenvalue=  
-2.507767E-01.
-P-0000   Action : change occopt, consistently, in GS and RF calculations.
-P-0000
-P-0000  leave_new : decision taken to exit ...
-P-0000  leave_new : synchronization done...
-P-0000  leave_new : exiting...