Mixed crystal formation and structural studies in the mullite-type system Bi{sub 2}Fe{sub 4}O{sub 9}-Bi{sub 2}Mn{sub 4}O{sub 10}

Journal Article · Sun Jan 15 00:00:00 EST 2012 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2011.10.046· OSTI ID:21612851

Kann, Zachary R; Auletta, Jeffrey T; Hearn, Eric W ^[1]; Weber, Sven-U; Becker, Klaus D ^[2]; Schneider, Hartmut ^[3]

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1. Department of Chemistry, University of North Florida, 1 UNF Drive, Jacksonville, FL 32224 (United States)
2. Institute of Physical and Theoretical Chemistry, Technische Universitaet Braunschweig, D-38106 Braunschweig (Germany)
3. Institute of Crystallography, Universitaet zu Koeln, 50939 Koeln (Germany)

The limits of metal cation substitution and distribution in the sequence Bi{sub 2}Fe{sub 4}O{sub 9}-Bi{sub 2}Mn{sub 4}O{sub 10} have been investigated by solid state synthesis, X-ray powder diffraction, and Moessbauer spectroscopy. Rietveld refinements conducted for the entire range along the join indicate the structures are orthorhombic with space group Pbam, with partial transition-metal site disorder confirmed and detailed by Moessbauer spectroscopy. Single-phase regions are found near each end-member and a two-phase region is observed at intermediate compositions, extending from about x=1 to 3, according to the general formula of the mixed crystals Bi{sub 2}Fe{sub 4-x}Mn{sub x}O{sub 10-{delta}}. An incorporation of Mn at octahedral sites replacing Fe is taken into account for the Bi{sub 2}Fe{sub 4}O{sub 9}-related side of the system. Charge compensation is believed to be effected by addition of O, which gives rise to the formation of FeO{sub 5} pyramids. At the Bi{sub 2}Mn{sub 4}O{sub 10}-related side of the system, substitution of pyramidal Mn{sup 3+} by Fe{sup 3+} is envisaged. - Graphical abstract: Single-phase regions are found near each end-member and a two-phase region is observed at intermediate compositions, extending from about x=1 to 3, according to the general formula of the mixed crystals Bi{sub 2}Fe{sub 4-x}Mn{sub x}O{sub 10-{delta}}. Highlights: Black-Right-Pointing-Pointer Mixed crystals of the mullite-type Bi{sub 2}Fe{sub 4-x}Mn{sub x}O{sub 10-{delta}} were synthesized. Black-Right-Pointing-Pointer Two single-phase regions and an intermediate two-phase region were found. Black-Right-Pointing-Pointer Site substitution was examined via X-ray diffraction and Moessbauer spectroscopy. Black-Right-Pointing-Pointer Charge compensation models were examined for intermediate compositions.

• OSTI ID: 21612851
• Journal Information: Journal of Solid State Chemistry, Vol. 185; Other Information: DOI: 10.1016/j.jssc.2011.10.046; PII: S0022-4596(11)00588-3; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CRYSTALS
DISTRIBUTION
MOESSBAUER EFFECT
MULLITE
ORTHORHOMBIC LATTICES
OXIDES
SOLID SOLUTIONS
SOLIDS
SPACE GROUPS
SYNTHESIS
X-RAY DIFFRACTION
CHALCOGENIDES
COHERENT SCATTERING
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DIFFRACTION
DISPERSIONS
HOMOGENEOUS MIXTURES
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
MATERIALS
MINERALS
MIXTURES
OXIDE MINERALS
OXYGEN COMPOUNDS
SCATTERING
SOLUTIONS
SYMMETRY GROUPS