Electronic structure of La2CuO4 in the self-interaction-corrected density-functional formalism.

Abstract

The electronic structure of tetragonal ${\mathrm{La}}_{2}$${\mathrm{CuO}}_{4}$ is calculated in the self-interaction-corrected (SIC) local-spin-density (LSD) approximation. In contrast to LSD, the SIC-LSD approach reveals the experimentally observed antiferromagnetic and semiconducting ground state. The energy gap is 1.04 eV and of indirect charge-transfer character, and the Cu moment is 0.47${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$. The valence-band top states have about equal weight on the in-plane and out-of-plane O atoms. This region is dominated by O states not coupling to the Cu d states, but with a significant component of O states having Cu d-like symmetry.