Acceptor-bound holes in oxides often localize asymmetrically at one out of
several equivalent oxygen ligands. Whereas Hartree-Fock (HF) theory overly
favors such symmetry-broken polaronic hole-localization in oxides, standard
local density (LD) calculations suffer from spurious delocalization among
several oxygen sites. These opposite biases originate from the opposite
curvatures of the energy as a function of the fractional occupation number n,
i.e., d2E/dn2 0 in LD. We recover the correct linear
behavior, d2E/dn2 = 0, that removes the (de)localization bias by formulating a
generalized Koopmans condition. The correct description of oxygen
hole-localization reveals that the cation-site nominal single-acceptors in ZnO,
In2O3, and SnO2 can bind multiple holes