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[taoj0003@ntu.edu.sg]

Dear abinit user

I used abinit to calcualte the band structure of rutile tio2. The band gap I 
get is around 5.3eV(9.17179-3.90134), while the experiment value is around 
3.2eV. I am very confused about this. Can any me help me check my input file?
Also the appropate output file is given. (The kpt I am giving is called #17, 
but I confirm I checked all the kpt.) btw, the pseudopotetials I am using are 
ti_ps.abinit.paw.lda and o_ps.abinit.paw.lda.nocore. I am always thinking 
maybe it's the pseudopotetials. Can any one help check this?
-----------------
input file
------------------
ndtset 2
 
#Dataset 1 : usual self-consistent calculation
kptopt1 1           
ngkpt1  4 4 6  
prtden1  1        
toldfe1  1.0d-6

#Dataset 2 : the band structure
iscf2    -2
getden2  -1
kptopt2  -2
nband2   32
ndivk2     18 14 
kptbounds2  
             0.0  0.5  0.5   # R point
             0.0  0.0  0.0 # Gamma point
             0.5  0.5  0.0 # M point

tolwfr2  1.0d-12
enunit2  1             # Will output the eigenenergies in eV 

acell 2*4.595 2.9589 angstrom
ntypat 2  
znucl 22 8  
 
natom 6  
typat 1 1 2 2 2 2  
xred  
  0.00000000  0.00000000   0.00000000      #Ti
  0.50000000  0.50000000   0.50000000      #Ti
  0.30530000  0.30530000   0.00000000      #O
  -0.30530000 -0.30530000  0.00000000      #O
  0.80530000  0.19470000   0.50000000      #O
  0.19470000  0.80530000   0.50000000      #O

#Definition of the planewave basis set
ecut 20.0         # Maximal kinetic energy cut-off, in Hartree

#Definition of the SCF procedure
nstep 10          # Maximal number of SCF cycles
diemac 2.0       

-------------------------------
the output file:
-----------------------------
kpt#  17, nband= 32, wtk=  1.00000, kpt=  0.0000  0.0556  0.0556 (reduced 
coord)
 -58.25568 -58.24540 -22.95254 -22.95190 -22.41545 -22.41462 -22.33658 
-22.24695  -14.01464 -12.73354 -11.18070 -11.17093  -1.71983  -0.89610  
-0.83583   0.58022    0.58350   2.02542   2.04408   2.50084   3.33573   
3.51918   3.52216   3.90134           9.17179   9.49369  10.42985  10.81380  
10.81895  12.04120  13.00632  13.58343