BaSn{sub 6}Co{sub 6}O{sub 19}-A novel frustrated antiferromagnet with the magnetoplumbite type structure

• Published in: Journal of solid state chemistry 2011-12, Vol.184 (12)
• Main Authors: Shlyk, L., Niewa, R.
• Format: Article
• Language: English
• Subjects: ALKALINE EARTH METAL COMPOUNDS; ANISOTROPY; ANTIFERROMAGNETISM; BARIUM CHLORIDES; BARIUM COMPOUNDS; BARIUM HALIDES; CHARGED PARTICLES; CHLORIDES; CHLORINE COMPOUNDS; COBALT IONS; COHERENT SCATTERING; CRYSTAL LATTICES; CRYSTAL STRUCTURE; CRYSTALLOGRAPHY; CRYSTALS; DIFFRACTION; DIMENSIONS; HALIDES; HALOGEN COMPOUNDS; HCP LATTICES; HEXAGONAL LATTICES; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; IONS; MAGNETIC PROPERTIES; MAGNETIC SUSCEPTIBILITY; MAGNETISM; MATHEMATICS; MINERALS; MONOCRYSTALS; OXIDE MINERALS; PHYSICAL PROPERTIES; SCATTERING; SPACE GROUPS; SPINELS; SYMMETRY GROUPS; TEMPERATURE DEPENDENCE; THICKNESS; TOPOLOGY; X-RAY DIFFRACTION
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2011.09.028

Single crystals of the novel compound BaSn{sub 6}Co{sub 6}O{sub 19} with maximum width 1 mm and thickness around 0.05 mm were grown from a barium chloride flux. The composition was determined from refinements of single crystal X-ray diffraction data and microprobe analysis. BaSn{sub 6}Co{sub 6}O{sub 19} crystallizes in the magnetoplumbite type structure (hexagonal, space group P6{sub 3}/mmc, a=6.0940(1) A, c=23.9633(5) A, V=770.69 A{sup 3}, Z=2). A significant disorder is generated by random occupation of two octahedrally coordinated crystallographic sites with Co{sup 2+} and Sn{sup 4+} ions, while further sites are exclusively occupied by either Co{sup 2+} (tetrahedrally coordinated) or Sn{sup 4+} (octahedrally coordinated). One site with mixed occupation realizes the topology of a kagome net. The temperature dependence of the magnetic susceptibility for a single crystal BaSn{sub 6}Co{sub 6}O{sub 19} reveals a low temperature antiferromagnetic order at T{sub N}=14 K. A relatively large value of frustration factor f{sub ||=}|{Theta}{sub W||}|/T{sub N} Almost-Equal-To 26 and f{sub Up-Tack }=|{Theta}{sub W Up-Tack }|/T{sub N} Almost-Equal-To 12 implies a frustrated antiferromagnetism. - Graphical abstract: Single crystals of novel magnetoplumbite BaSn{sub 6}Co{sub 6}O{sub 19} have been characterized. Highlights: Black-Right-Pointing-Pointer A novel compound magnetoplumbite BaSn{sub 6}Co{sub 6}O{sub 11} is synthesized in single crystalline form. Black-Right-Pointing-Pointer It contains structural subunits with kagome topology, sandwiched between spinel blocks. Black-Right-Pointing-Pointer Structural disorder in both subunits by random replacement of magnetic Co{sup 2+} with nonmagnetic Sn{sup 4+}. Black-Right-Pointing-Pointer Bulk magnetic measurements indicate long-range antiferromagnetic order below 14 K. Black-Right-Pointing-Pointer The anisotropic frustration factor indicates strongly frustrated antiferromagnetism.