Neutron diffraction results for three-layer aurivillius phase containing magnetic transition metal cations: Ru (IV), Ir (IV) and Mn (IV)

Abstract

The synthesis and characterisation of three-layer Aurivillius-type phases containing magnetic cations M4+ (M = Ru, Ir, Mn), based on the substitution M4+ for Ti4+ in Bi2Sr2(Nb,Ta)2TiO12 has recently been reported [1]. These structures show the partial substitution of Sr2+ for Bi3+ in the [Bi2O2]2+ layers that results in the decrease of M4+ content; the compositions prepared were Bi2-xSr2+x(Nb,Ta)2+xM1-xO12, x ≈ 0.5. This work looks at the neutron diffraction of these samples and shows the existence of a symmetry-lowering mode.