Please use this identifier to cite or link to this item:
Title: Anomalous lattice parameter increase in alkali earth aluminium substituted tungsten defect pyrochlores
Authors: Thorogood, GJ
Kennedy, BJ
Peterson, VK
Elcombe, MM
Kearley, GJ
Hanna, JV
Luca, V
Keywords: Lattice parameters
Alkaline earth metal compounds
Neutron diffraction
Diffuse scattering
Issue Date: Mar-2009
Publisher: Elsevier
Citation: Thorogood, G. J., Kennedy, B. J., Peterson, V. K., Elcombe, M. M., Kearley, G. J., Hanna, J. V., & Luca, V. (2009). Anomalous lattice parameter increase in alkali earth aluminium substituted tungsten defect pyrochlores. Journal of Solid State Chemistry, 182(3), 457-464. doi:10.1016/j.jssc.2008.11.014
Abstract: The structures of the defect pyrochlores AAl(0.33)W(1.67)O(6) where A = K, Rb or Cs have been investigated using X-ray and neutron powder diffraction methods as well as the ab initio modelling program VASP The three cubic pyrochlores exhibit a non-linear increase in lattice parameter with respect to ionic radius of the A cation as a consequence of displacive disorder of the A-type cations. Solid state Al-27 MAS NMR studies of this pyrochlore system reveal shifts in the delta-21-22 ppm range that are indicative of pseudo-5 coordinate Al environments and emanate frorn distorted Al octahedral with one abnormally long Al. O bond. Solid state K-39, Rb-85, Rb-87 and Cs-133 MAS and static NMR Studies reflect the local cation disorder demonstrated in the structural Studies. © 2008, Elsevier Ltd.
Gov't Doc #: 1254
ISSN: 0022-4596
Appears in Collections:Journal Articles

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.