Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-08T05:33:37.710Z Has data issue: false hasContentIssue false
  • English
  • Français

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 ,
Shiho Suehiro ,
Toru Asaka ,
Hiromi Nakano  and
Koichiro Fukuda
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: [email protected]
Get access Rights & Permissions [Opens in a new window]

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.

Keywords

lithium tantalatex-ray powder diffractionRietveld methodphosphor
Type
Technical Articles
Information
Powder Diffraction , Volume 28 , Issue 3 , September 2013 , pp. 178 - 183
Copyright
Copyright © International Centre for Diffraction Data 2013 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abrahams, S. C. and Bernstein, J. L. (1967). “Ferroelectric lithium tantalate–1. single crystal X-ray diffraction study at 24°C,” J. Phys. Chem. Solids 28, 1685–1692.CrossRefGoogle Scholar
Abrahams, S. C., Hamilton, W. C., and Sequeira, A. (1967). “Ferroelectric lithium tantalate–2. Single crystal neutron diffraction study at 24°C,” J. Phys. Chem. Solids 28, 1693–1698.CrossRefGoogle Scholar
Balic-Zunic, T. and Vickovic, I. (1996). “IVTON – a program for the calculation of geometrical aspects of crystal structures and some crystal chemical applications,” J. Appl. Crystallogr. 29, 305–306.CrossRefGoogle Scholar
Brese, N. E. and O'Keeffe, M. (1991). “Bond-valence parameters for solids,” Acta Crystallogr., Sect. B: Struct. Sci. 47, 192–197.CrossRefGoogle Scholar
Brown, I. D. and Altermatt, D. (1985). “Bond-valence parameters obtained from a systematic analysis of the inorganic crystal structure database,” Acta Crystallogr., Sect. B: Struct. Sci. 41, 244–247.CrossRefGoogle Scholar
Hsu, R., Maslen, E. N., Du Boulay, D., and Ishizawa, N. (1997). “Synchrotron X-ray studies of LiNbO3 and LiTaO3,” Acta Crystallogr. B Struct. Sci. 53, 420–428.CrossRefGoogle Scholar
Izumi, F. (2004). “Beyond the ability of Rietveld analysis: MEM-based pattern fitting,” Solid State Ion. 172, 1–6.CrossRefGoogle Scholar
Izumi, F., Kumazawa, S., Ikeda, T., Hu, W.-Z., Yamamoto, A., and Oikawa, K. (2001). “MEM-based structure-refinement system REMEDY and its applications,” Mater. Sci. Forum 378–381, 59–64.CrossRefGoogle Scholar
Izumi, F. and Momma, K. (2007). “Three-dimensional visualization in powder diffraction,” Solid State Phenom. 130, 15–20.CrossRefGoogle Scholar
Izumi, F. and Momma, K. (2010). “Analyses of magnetic structures and nuclear-density distribution by the structure-refinement and three-dimensional visualization systems RIETAN-FP-VENUS (in Japanese),” J. Vac. Soc. Jpn 53, 706–712.CrossRefGoogle Scholar
Makovicky, E. and Balic-Zunic, T. (1998). “New measure of distortion for coordination polyhedra,” Acta Crystallogr. B Struct. Sci. B54, 766–773.CrossRefGoogle Scholar
Megaw, H. D. (1973). Crystal Structures: A Working Approach (W. B. Saunders Company, Philadelphia). pp. 233–241.Google Scholar
Momma, K. and Izumi, F. (2008). “VESTA: A three-dimensional visualization system for electronic and structural analysis,” J. Appl. Crystallogr. 41, 653–658.CrossRefGoogle Scholar
Nakano, H., Ozono, K., Hayashi, H. and Fujihara, S. (2012). “Synthesis and luminescent properties of a new Eu3+-Doped Li1+x(Ta1−zNbz)1−xTixO3 red phosphor,” J. Am. Ceram. Soc. 95, 2795–2797.CrossRefGoogle Scholar
Ohgaki, M., Tanaka, K., and Marumo, F. (1989). “Anharmonic thermal vibration in a crystal of lithium(I) tantalum(V) trioxide, LiTaO3,” Mineral. J. 14, 373–382.CrossRefGoogle Scholar
Rietveld, H. M. (1967). “Line profiles of neutron powder-diffraction peaks for structure refinement,” Acta Crystallogr. 22, 151–152.CrossRefGoogle Scholar
Shannon, R. D. (1976). “Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr. A32, 751–767.CrossRefGoogle Scholar
Takata, M., Nishibori, E., and Sakata, M. (2001). “Charge density studies utilizing powder diffraction and MEM. Exploring of high Tc superconductors, C60 superconductors and manganites,” Z. Kristallogr. 216, 71–86.CrossRefGoogle Scholar
Toraya, H. (1990). “Array-type universal profile function for powder pattern fitting,” J. Appl. Crystallogr. 23, 485–491.CrossRefGoogle Scholar
Young, R. A. (1993). “Introduction to the Rietveld method,” in The Rietveld Method, edited by Young, R. A. (Oxford University Press, Oxford, UK), pp. 1–38.CrossRefGoogle Scholar