[Pw_forum] DFT+U convergence

[Giuseppe Mattioli]

Dear Zarah
It's a kind of semiempirical (not a kind of magic, anyway...:-)), but  
when you deal with metal oxides you may try to correct with +U the O  
2p shell. Sometimes the DFT+U(metal,oxygen) approach helps to reach  
convergence more smoothly than DFT+U(metal). You may want to look at

Himmetoglu, B.; Floris, A.; de Gironcoli, S.; Cococcioni, M. Int. J.  
Quantum Chem. 2014, 114, 14-49.
Mattioli, G.; Alippi, P.; Filippone, F.; Caminiti, R.; Amore  
Bonapasta, A. J. Phys. Chem. C 2010, 21694-21704, 114.

HTH

Giuseppe

Giuseppe Mattioli
ISM-CNR
Italy

Quoting Zarah Baiyee <z.baiyee at gmail.com>:

> Dear All,
>
> I am working on a perovskite system, BaFeO3, and trying to include a
> hubbard correction for the Fe cation, yet struggling with convergence. I
> have read on previous posts, that convergence can be difficult using the
> pbe x-change correlation, therefore I have tried both with my initial pbe
> PPs and LDA PPs yet still struggling.
>
> Please find attached, the input files any advice would be much appreciated.
>
> Kind Regards
>
> Zarah


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    Giuseppe Mattioli
    CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
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