Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1492286 | Materials Research Bulletin | 2006 | 14 Pages |
The magnetic ferroelectric double perovskite Sr2NiMoO6 has been characterised using neutron powder diffraction (NPD) data and magnetic susceptibility measurements. High temperature NPD data indicate that the material undergoes a continuous structural phase transition from tetragonal (I4/m) to cubic (Fm 3¯m) at approximately 550 K. The transition is linked to the level of rotation of the NiO6 and MoO6 octahedra, which form perfectly segregated sub-lattices in the material. The reduction in symmetry at 550 K is linked to the onset of a spontaneous dipole in the material allowing the structural perturbation to be described as an improper ferroelectric phase transition. The appearance of low angle reflections in the 20 K dataset indicates the presence of an antiferromagnetic ordered ground state. The magnetic moment was refined to 1.88(8) μB confirming that the magnetism originates from the Ni2+ (S = 1) ions.