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[lsl0426@yahoo.com]

Hi everybody,

I try to calculate Phonon of magnetic material Fe3O4, but I got very strange 
answer. My phonon frequencies are all negative!! Could abinit do phonon 
calculation of magnetic materials ? I need some
suggections.

Thanks in advence.

Shihn-lun.

----Here is my input file----------------------------------------------------
(My abinit version is 4.3.3)

ndtset 3

#Ground state calculation
  kptopt1   1
  tolvrs1   1.0d-18
    iscf1   5
  prtden1   1
  prtdos1   2

#Non-self consistent ground-state calculation
    nqpt2   1
     qpt2   0.5 0.0 0.5
  getwfk2   1
  getden2   1
  kptopt2   3
    iscf2  -2
  tolwfr2   1.0d-18

#Response Function calculation
  rfphon3   1
 rfatpol3   1 14
   rfdir3   1 1 1
    nqpt3   1
     qpt3   0.5 0.0 0.5
  getwfk3   1
  getwfq3   -1
  kptopt3   3
  tolvrs3   1.0d-8
    iscf3   5

#Common data
 ngkpt 4 4 4
 ecut  25
 acell 3*11.21479
 nband 76
 ixc    1
 natom  14
 nstep  100
 ntypat 2
 nline  5
 occopt 4
 tsmear 0.01
 nsppol 2
 angdeg 60 60 60
 typat  8*1 6*2
 znucl 8 26

#My atomic position was relaxed.

 xred  3.8041109137E-01  3.8041109137E-01  3.8041109137E-01
       1.3804110914E+00  3.8041109137E-01 -1.1412332741E+00
       3.8041109137E-01 -1.1412332741E+00  1.3804110914E+00
      -1.1412332741E+00  1.3804110914E+00  3.8041109137E-01
      -1.3041109137E-01  8.6958890863E-01  1.3912332741E+00
      -1.3041109137E-01 -1.3041109137E-01 -1.3041109137E-01
       8.6958890863E-01  1.3912332741E+00 -1.3041109137E-01
       1.3912332741E+00 -1.3041109137E-01  8.6958890863E-01
      -1.3877787808E-17  0.0000000000E+00  6.4704046281E-38
       2.5000000000E-01  1.2500000000E+00  2.5000000000E-01
       6.2500000000E-01  6.2500000000E-01  6.2500000000E-01
       1.6250000000E+00  6.2500000000E-01 -1.8750000000E+00
       6.2500000000E-01 -1.8750000000E+00  1.6250000000E+00
      -1.8750000000E+00  1.6250000000E+00  6.2500000000E-01

 spinat
     0 0 0
     0 0 0
     0 0 0
     0 0 0
     0 0 0
     0 0 0
     0 0 0
     0 0 0
     0 0 -4
     0 0 -4
     0 0 4
     0 0 4
     0 0 4
     0 0 4

---- Here is my phonon frequencies--------------------------------------------
 Phonon frequencies in cm-1    :
- -2.348448E+03 -2.341367E+03 -1.948436E+03 -1.942066E+03 -1.790000E+03
- -1.789706E+03 -1.786107E+03 -1.785757E+03 -1.777137E+03 -1.776651E+03
- -1.759038E+03 -1.757601E+03 -1.658417E+03 -1.658145E+03 -1.654716E+03
- -1.652842E+03 -1.452359E+03 -1.447867E+03 -1.435041E+03 -1.434391E+03
- -1.433424E+03 -1.430241E+03 -1.428843E+03 -1.427855E+03 -1.423852E+03
- -1.422391E+03 -1.418350E+03 -1.417425E+03 -1.409389E+03 -1.405311E+03
- -1.398663E+03 -1.398317E+03 -1.393078E+03 -1.390478E+03 -1.240919E+03
- -1.236351E+03 -1.232696E+03 -1.228577E+03 -1.217993E+03 -1.217587E+03
- -1.205610E+03 -1.204469E+03


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