[Wien] LDA+U

[Peter Blaha]

The magnetic structure of NiO is Antiferromagnetic and for a proper
description you cannot use the NaCl structure.

You need a rhombohedral unit cell with 2 Ni atoms. 
in $WIENROOT/excample_struct_files there is a coo  (CoO) example.


> There is a problem that made me confuse a lot. I need your help.
> 
>  I performed the LDA+U calculation for NiO as an example. The structure file
> is as follow:
> 
> NiO
> F   LATTICE,NONEQUIV.ATOMS:  2225_Fm-3m
> MODE OF CALC=RELA unit=bohr
>   7.927000  7.927000  7.927000 90.000000 90.000000 90.000000
> ATOM   1: X=0.00000000 Y=0.00000000 Z=0.00000000
>           MULT= 1          ISPLIT= 2
> Ni          NPT=  781  R0=0.00010000 RMT=    2.0000   Z: 28.0
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                                   0.0000000 1.0000000 0.0000000
>                               0.0000000 0.0000000 1.0000000
> ATOM   2: X=0.50000000 Y=0.00000000 Z=0.00000000
>           MULT= 1          ISPLIT= 2
> O         NPT=  781  R0=0.00010000 RMT=    2.0000   Z: 8.0
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                                   0.0000000 1.0000000 0.0000000
>                                   0.0000000 0.0000000 1.0000000
> 
> NiO.indm
> 
> -9
> 1
> 1 1 2
> 0 0
> 
> NiO.inorb
> 1 2 0
> PRATT 0.5
> 1 1 2
> 1
> 0.52  0.00
> 
> By this set up, everything ran well. But I'm not sure that it is right or
> wrong.
> 
> But if I set up Ni as atom 2 and O as atom 1:
> 
> Title
> F   LATTICE,NONEQUIV.ATOMS:  2225_Fm-3m
> MODE OF CALC=RELA unit=bohr
>   7.927000  7.927000  7.927000 90.000000 90.000000 90.000000
> ATOM   1: X=0.50000000 Y=0.00000000 Z=0.00000000
>           MULT= 1          ISPLIT= 2
> O          NPT=  781  R0=0.00010000 RMT=    1.6500   Z:  8.0
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                      0.0000000 1.0000000 0.0000000
>                      0.0000000 0.0000000 1.0000000
> ATOM   2: X=0.00000000 Y=0.00000000 Z=0.00000000
>           MULT= 1          ISPLIT= 2
> Ni         NPT=  781  R0=0.00010000 RMT=    2.0000   Z: 28.0
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                      0.0000000 1.0000000 0.0000000
>                      0.0000000 0.0000000 1.0000000
> 
> 
> NiO.indm
> 
> -9
> 1
> 2 1 2
> 0 0
> 
> NiO.inorb
> 1 1 0
> PRATT 0.5
> 2 1 2
> 1
> 0.52  0.00
> 
> I met the error
> 
> 
>    cycle 1      (Tue Aug 30 17:16:33 SGT 2005)  (60/40 to go)
> 
> >   lapw0 -p    (17:16:33) starting parallel lapw0 at Tue Aug 30 17:16:33 SGT
> 2005
> --------
> running lapw0 in single mode
> 2.369u 0.117s 0:02.48 99.5%     0+0k 0+0io 0pf+0w
> >   orb -up -p  (17:16:35) 0.003u 0.002s 0:00.00 0.0%   0+0k 0+0io 0pf+0w
> 
> >   stop error
> 
>  I really do not understand why it crashed in this case. Did I set up the
> input files wrongly?
> 
>  Looking at the user guide page 80 and the lecture note by Novak the LDA+U
> calculation was set up for two different Ni atoms with different index 1 and
> 2. The question is: should we need two different Ni atoms for LDA+U?
> 
>  Many thanks for help.
> 
> Regards,
> Khuong
> 


                                      P.Blaha
--------------------------------------------------------------------------
Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
--------------------------------------------------------------------------