[Wien] Need advice for modeling the band gap in a charge transfer insulator

[shamik chakrabarti]

Dear wien2k users,

                            We all know that LSDA (or GGA)+U can be used
successfully for a Mott-Hubbard insulator. Anisimov et al. [PRL 99, 156404
(2007)] have described that for a charge transfer insulator we need to use
LDA+DMFT for modelling their band structure properly. Now my question is :

(1) Is their any option in wien2k by which we can use LDA+DMFT?

(2) In our calculation after applying GGA+U (U for d orbital of TM) we saw
that although there are a band gap between spin up & spin dn d DOS of
transition metal, there are ligand (O p) DOS at Fermi Energy which is making
our material metallic while experimentally it is an insulator [conductivity
~ 10^(-7)]. Here should we apply some value of U (say 0.15 Ry) for O p
orbital also?

(3) Any other advice regarding to this problem will be highly appreciated.

Thanks in advance.

yours faithfully,
-- 
Shamik Chakrabarti
Senior Research Fellow
Dept. of Physics & Meteorology
Material Processing & Solid State Ionics Lab
IIT Kharagpur
Kharagpur 721302
INDIA
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