Stoichiometry and oxygen structure of Fe sillenite

Abstract The sillenite phase in the Bi 2 O 3 -Fe 2 O 3 system has been characterized by X-ray, infrared absorption and magnetic susceptibility measurements. The composition corresponded to a concentration of 3.7 ± 0.2 mol% Fe 2 O 3 only compatible with a Bi 25 FeO 40 stoichiometry. A powder neutron diffraction study provided structural information on the oxygen lattice.