Structure determination of {alpha}-La{sub 6}W{sub 2}O{sub 15}

Journal Article · Tue Jun 15 00:00:00 EDT 2010 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2010.03.043· OSTI ID:21421514

Chambrier, M-H ^[1]; Ibberson, R M ^[2]; Goutenoire, F ^[1]

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1. Laboratoire des Oxydes et Fluorures, UMR-CNRS 6010, Universite du Maine, 72085 Le Mans Cedex 9 (France)
2. ISIS Facility, STFC-Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX (United Kingdom)

The structure of the high temperature alpha form of La{sub 6}W{sub 2}O{sub 15} has been determined ab-initio from high temperature laboratory X-ray and neutron time-of-flight data. This tungstate crystallizes in the non-centrosymmetric orthorhombic space group (No. 20) C222{sub 1}, with Z=2, a=12.6250(2) A, b=9.1875(1) A, c=5.9688(1) A. The structure comprises [O{sub 2}La{sub 3}] infinite ribbons and is better described by the structural formula [O{sub 2}La{sub 3}]{sub 2}[WO{sub 5.5}]{sub 2}. Using this description we can understand the strong structural similarity of the present compound with compounds of the general composition BiM{sub 2}AO{sub 6} (M=Cu, Mg, Zn, Mn, Cd, Ca, Pb; A=P, As, V) described as [O{sub 2}M{sub 2}Bi][AO{sub 4}]. The [WO{sub 5.5}] entity implies oxygen disorder in the material. - Graphical abstract: Projection of the polyhedra around the tungsten atom. Atoms labelled in grey are occupied at 50%. Short oxygen-oxygen distances are marked. The polyhedra represents WO{sub 5.5} that is related to the structural unit W{sub 2}O{sub 11} unit. Alpha-La{sub 6}W{sub 2}O{sub 15} could be described as [O{sub 2}La{sub 3}]{sub 2}[WO{sub 5.5}]{sub 2}.

• OSTI ID: 21421514
• Journal Information: Journal of Solid State Chemistry, Vol. 183, Issue 6; Other Information: DOI: 10.1016/j.jssc.2010.03.043; PII: S0022-4596(10)00133-7; Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
LANTHANUM COMPOUNDS
NEUTRON DIFFRACTION
ORTHORHOMBIC LATTICES
OXIDES
PHASE TRANSFORMATIONS
SPACE GROUPS
TIME-OF-FLIGHT METHOD
TUNGSTATES
X-RAY DIFFRACTION
CHALCOGENIDES
COHERENT SCATTERING
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DIFFRACTION
OXYGEN COMPOUNDS
RARE EARTH COMPOUNDS
REFRACTORY METAL COMPOUNDS
SCATTERING
SYMMETRY GROUPS
TRANSITION ELEMENT COMPOUNDS
TUNGSTEN COMPOUNDS