Oxygen vacancies and antiferromagnetism inLa2CuO4

Abstract

Self-consistent spin-polarized band-structure calculations have been carried out on stoichiometric ${\mathrm{La}}_2$ ${\mathrm{CuO}}_4$ and two ordered oxygen-vacancy supercells corresponding to ${\mathrm{La}}_2$ ${\mathrm{CuO}}_{3.75}$. Both the tetragonal and orthorhombic structures are considered. No stable antiferromagnetic moment is found and the presence of oxygen vacancies appears to further reduce any tendency to antiferromagnetic ordering. Ba and Sr doping are also shown to reduce antiferromagnetism.