Frustrated magnetism and local structural disorder in pyrochlore-type Bi1.89Fe1.16Nb0.95O6.95

• Published in: Journal of physics. Condensed matter Vol. 22; no. 48; p. 486004
• Main Authors: Miiller, W, Causeret, L, Ling, C D
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 08.12.2010; Institute of Physics
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Growth from melts; zone melting and refining; Magnetic properties and materials; Magnetically ordered materials: other intrinsic properties; Materials science; Methods of crystal growth; physics of crystal growth; Physics; Saturation moments and magnetic susceptibilities; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; Spin glasses; Electron pairs; Coexistence; XRD; Floating zone; Pyrochlore type compound; Magnetic susceptibility; Local structure; Monocrystals; Growth mechanism; Magnetism; Crystal growth from melts; Magnetic properties
• ISSN: 0953-8984; 1361-648X
• DOI: 10.1088/0953-8984/22/48/486004

The magnetic properties of pyrochlore-type Bi(1.89)Fe(1.16)Nb(0.95)O(6.95) have been investigated for the first time using AC and DC susceptibility. The compound is shown to behave as a classical spin glass due to strong competition/coexistence of ferro- and antiferromagnetic exchange. The study was accompanied by the first-ever growth of single crystals of this compound using the floating-zone method, allowing us to carry out a single-crystal neutron diffraction experiment that confirmed and extended our understanding of local structural disorder, driven by the stereochemically active 6s(2) electron lone pair on Bi(3+) ions. The magnetic properties are discussed in terms of both the topologically frustrated Fe(3+) lattice and the role of this local structural disorder.