[Pw_forum] multiples site Hubbard U

[Tommaso Francese]

Dear all, 
i’m working on a Yttria doped Zirconia, YSZ. I have understood how to calculate the U values for a single site, but how can i calculate the U values for both the transition metal inside the same structure, e.g. Zr and Y in YSZ structure? Do i have to build a supercell even in this case?
Thanks in advance,
Tommaso Francese.
Università Cà Foscari of Venice.