Chromium dioxide (CrO₂) has been extensively used in the magnetic recording industry. However, it is its ferromagnetic half-metallic nature that has more recently attracted much attention, primarily for the development of spintronic devices. CrO₂ is the only stoichiometric binary oxide theoretically predicted to be fully spin polarized at the Fermi level. It presents a Curie temperature of ∼ 396 K, i.e. well above room temperature, and a magnetic moment of 2 mB per formula unit. However an antiferromagnetic native insulating layer of Cr₂O₃ is always present on the CrO₂ surface which enhances the CrO₂ magnetoresistance and might be used as a barrier in magnetic tunnel junctions.