Structural and magnetic properties of Nd18Li8Co4--xFexO3-y and Nd18Li8Co4-xTixO39-y

Journal article

Nd18Li8Co3FeO39-y, Nd 18Li8CoFe3O39-y and Nd 18Li8Co3TiO39-y have been synthesised and characterised by neutron powder diffraction, magnetometry and Mössbauer spectroscopy. Their cubic structure (Pm3n, a∼11.9 Å) is based on intersecting <1 1 1> chains comprised of alternating octahedral and trigonal-prismatic coordination sites. These chains lie within hexagonal-prismatic cavities formed by a NdO framework. Each compound has an incomplete oxide sublattice (y∼1), with vacancies located around the octahedral sites that lie at the points of chain intersection. These sites are fully occupied by a disordered arrangement of transition-metal cations but only 75% of the remaining octahedral sites are occupied. The trigonal-prismatic sites are fully occupied by lithium except in the case of Nd18Li 8CoFe3O39-y where some iron is present. Antiferromagnetic interactions are present on the Nd sublattice in each composition, but a spin glass forms below 5 K when a high concentration of spins is also present on the octahedral sites. © 2011 Elsevier Inc.

Authors: Battle, P; Dutton, SE; Grandjean, F; Long, G; Thammajak, N

• Publication status: Published
• Journal: JOURNAL OF SOLID STATE CHEMISTRY
• Volume: 184
• Issue: 9
• Pages: 2580-2587
• Publication date: 2011-09-01
• DOI: 10.1016/j.jssc.2011.07.020
• EISSN: 1095-726X
• ISSN: 0022-4596
• Language: English
• Keywords: Antiferromagnetism; Mixed-metal oxides; Spin glass; Neutron diffraction