[Pw_forum] about GGA+U calculation

[Paolo Giannozzi]

On Wed, 2014-12-24 at 10:41 +0530, Bipul Rakshit wrote:
> 
> I am doing GGA+U calculation for ZnO wurtzite structure. I attached
> the input file for the same.
> My doubt is for using "Hubbard U" we are using two additional tags
> (compared to simple GGA calculation) 
>                lda_plus_u = .true.,
>               Hubbard_U(1) =8.0, Hubbard_U(2)=0.0,

> So I am applying Hubbard U=8 eV on my first species (i.e. Zn) and 0.0
> eV on Oxygen.
> But how can I understand that this Hubbard U of 8 eV is applied on Zn-
> d states?

currently it is hard-coded: see flib/set_hubbard_l.f90;
PW/src/tabd.f90; PW/src/ldaU.f90, subroutine set_Hubbard_l

Paolo

-- 
Paolo Giannozzi, Dept. Chemistry&Physics&Environment, 
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222