The ABINIT Users Mailing List ( CLOSED )

["D. R. Hamann" <drhamann@mat-simresearch.com>]

Dear Vahid,

I think your basic problem is that you are trying to get 5 Wannier 
functions out of 40 bands, giving the program no guidance as to what 
bands can be reasonably disentangled, or what the atomic or bonding 
character of the WF's you seek might be.  For 16 atoms, the minimum 
number of WF's you might reasonably expect to disentangle would be the 
number of atoms of one type times the number of valance orbitals on that 
atom that can be reasonably grouped in an energy window.  This is a 
lower bound.  You need to then specify the disentanglement window 
(dis_win_min, dis_win_max) in the *.win file, and probably a guess as to 
the character of the functions you expect using (begin projections ... 
end projections) in that file.  The Wannier90 user's manual should help.

Best regards,
Don Hamann

Vahid Askarpour wrote:
> Dear Abinit Users,
>
> Using the wannier option of ABINIT 5.8.4, I get the following message in the 
> wannier90.wout file right after the disentanglement convergence section:
>
>  ERROR: IN ZGESVD IN dis_main
>  K-POINT NKP=           1  INFO=           4
>  Exiting.......
>  dis_main: problem in ZGESVD 1
>
> All the eigenvalues in wannier90.eig are infinity. My two input files are:
>
> File 1
>
> # HI structure
> ndtset  2
> kptopt  3            # Option for the automatic generation of k points,
> nkpt    512
> ngkpt   8 8 8
> nshiftk 1
> shiftk  0.0 0.0 0.0
> # Self-consistent run to get the density
> iscf1      5
> nstep1   300
> tolvrs1    1.00d-10 #Tolerance for convergence
> nband1   40
> prtden1   1
> diemac1  12.0     #Preconditioner for scf
> istwfk1    512*1     #Controls the form of the wavefunctions
> # Second: Wannier90
> iscf2     -2   #nscf run
> nstep2   0      #just read the old wave functions
> tolwfr2   1.e-10 
> getwfk2  1
> getden2 1   # Usual file handling data
> prtwant2 2   # Call to Wannier90
> nband2  40
> istwfk2  512*1 #Controls the form of the wavefunctions
> w90prtunk2 1   #Prints UNK files (for plotting the Wannier functions)
> # Definition of the unit cell: Triclinic
> acell 1.3652185228E+01  1.9310062579E+01  9.8097544562E+00
> angdeg 90.00000116  90.00000117  44.99121644
> strtarget -4.75846d-4 -4.75846d-4 -4.75846d-4 0 0 0
> occopt  7
> tsmear  0.01
> # Definition of the atom types
> ntypat  2         # There are two types of atom
> znucl 1 53
> # Definition of the atoms
> natom 16          # There are 16 atoms
> typat  1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2   # They  are of two types , that is, 
> H and I.
> xcart         4.4575393774E+00  1.9054055331E+00  1.1215044142E+01
>               9.4739271732E-01 -1.5347641011E+00  1.1215042652E+01
>               9.6571747909E-01  5.3983758496E+00  1.1215046211E+01
>              -2.4756193134E+00  1.8892786634E+00  1.1215044134E+01
>               4.4186330990E+00  1.8664452803E+00  6.3101667787E+00
>               7.8599773549E+00  5.3755345569E+00  6.3101627548E+00
>               4.4369740034E+00  8.7995863589E+00  6.3101642197E+00
>               9.2681947032E-01  5.3594230855E+00  6.3101687934E+00
>              -2.5251165030E+00 -1.5831110203E+00  1.1215016651E+01
>               4.5164792687E+00 -1.5906794232E+00  1.1215014128E+01
>               4.5172363318E+00  5.4567912155E+00  1.1215012544E+01
>              -2.5302436040E+00  5.4584964054E+00  1.1215015663E+01
>               8.6712054180E-01  1.8080285220E+00  6.3101375466E+00
>               7.9146019343E+00  1.8063244617E+00  6.3101372695E+00
>               7.9094736823E+00  8.8479293887E+00  6.3101379406E+00
>               8.6788045533E-01  8.8555031864E+00  6.3101381586E+00
> # Use only symmorphic operations
> symmorphi 0
> # Definition of the planewave basis set (at convergence 16 Rydberg 8 Hartree)
> ecut 25.0          # Maximal kinetic energy cut-off, in Hartree
>
>
> File 2 (wannier90.win)
>
> num_wann 5
> num_iter 300
> dis_num_iter 700
> dis_conv_tol 1.0E-7
> iprint 1
> !plotting
> wannier_plot =true
>
> I have used a 4x4x4 grid and got the same result. I'd appreciate any comments 
> or hints.
>
> Vahid Askarpour
>
>
>
>       
>
>   

--
D. R. Hamann
Mat-Sim Research LLC    | Department of Physics
P.O. Box 742            |  and Astronomy
Murray Hill, NJ 07974   | Rutgers University
phone: 908-370-8079     | 732-445-5500, x4381

email: drhamann@mat-simresearch.com