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Syntheses and crystal structures of Li(Ta0.89Ti0.11)O2.945 and (Li0.977Eu0.023)(Ta0.89Ti0.11)O2.968

Published online by Cambridge University Press:  24 April 2013

Tomohiro Uchida
Affiliation:
Department of Environmental and Materials Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
Shiho Suehiro
Affiliation:
Department of Environmental and Life Sciences, Toyohashi University of Technology, Toyohashi 441-8580, Japan
Toru Asaka
Affiliation:
Department of Environmental and Materials Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
Hiromi Nakano
Affiliation:
Department of Environmental and Life Sciences, Toyohashi University of Technology, Toyohashi 441-8580, Japan
Koichiro Fukuda*
Affiliation:
Department of Environmental and Materials Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
*
a)Author to whom correspondence should be addressed. Electronic mail: fukuda.koichiro@nitech.ac.jp

Abstract

Crystal structures of Li(Ta0.89Ti0.11)O2.945 and (Li0.977Eu0.023)(Ta0.89Ti0.11)O2.968 were investigated by laboratory X-ray powder diffraction. Both title compounds were trigonal with space group R3c and Z = 6. The hexagonal unit-cell dimensions were a = 0.514 82 9(2) nm, c = 1.377 61 2(4) nm, and V = 0.316 21 6(2) nm3 for the former compound and a = 0.517 71 2(2) nm, c = 1.373 50 0(6) nm, and V = 0.318 81 2(3) nm3 for the latter. The initial structural models, being isostructural with LiTaO3, were refined by the Rietveld method. The maximum-entropy method-based pattern fitting (MPF) method was subsequently used to confirm the validity of the structural models, in which conventional structure bias caused by assuming intensity partitioning was minimized. Atomic arrangements of the final structural models were in excellent agreement with the three-dimensional electron-density distributions determined by MPF.

Type
Technical Articles
Copyright
Copyright © International Centre for Diffraction Data 2013 

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