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Crystal structure of BaBi2Ta2O9

Published online by Cambridge University Press:  10 January 2013

Carlos O. Paiva-Santos ,
Talita Mazon ,
Maria A. Zaghete ,
André L. Campos ,
J. A. Varela  and
Cesar R. Foschini
Carlos O. Paiva-Santos
Affiliation:
Laboratório Computacional em Análises Cristalográficas e Cristalinas, LabCACC, Instituto de Química, UNESP, R. Prof. Francisco Degni s/n, 14800-900 Araraquara (SP), Brazil
Talita Mazon
Affiliation:
Laboratório Interdisciplinar em Cera⁁mica, LIEC, Instituto de Química, UNESP, R. Prof. Francisco Degni s/n, 14800-900 Araraquara (SP), Brazil
Maria A. Zaghete
Affiliation:
Laboratório Interdisciplinar em Cera⁁mica, LIEC, Instituto de Química, UNESP, R. Prof. Francisco Degni s/n, 14800-900 Araraquara (SP), Brazil
André L. Campos
Affiliation:
Laboratório Interdisciplinar em Cera⁁mica, LIEC, Instituto de Química, UNESP, R. Prof. Francisco Degni s/n, 14800-900 Araraquara (SP), Brazil
J. A. Varela
Affiliation:
Laboratório Interdisciplinar em Cera⁁mica, LIEC, Instituto de Química, UNESP, R. Prof. Francisco Degni s/n, 14800-900 Araraquara (SP), Brazil
Cesar R. Foschini
Affiliation:
Laboratório Interdisciplinar em Cera⁁mica, LIEC, Instituto de Química, UNESP, R. Prof. Francisco Degni s/n, 14800-900 Araraquara (SP), Brazil
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Abstract

The crystal structure of the Aurivillius compound Bi2BaTa2O9 prepared via the chemical route was determined by direct methods using EXPO97, and refined using the Rietveld method with conventional X-ray diffraction data. The structure was found to be tetragonal (space group I4/mmm, number 139) and Z=2, isomorphic of the Bi2BaNb2O9 reported by Blake and co-workers in the literature (1997). Two refinements were performed using the two asymmetry functions of DBWS-9807 (release 20/May/99). The unit cell for each case are: a=3.932 22(6) Å, c=25.5053(6) Å (RA) and a=3.932 50(7) Å, c=25.5069(6) Å (RCF). The differences for atom positions, interatomic distances and angles are in the range of one standard deviation. Final agreements factors are: Rwp=7.97%, S=1.84, RBragg=4.28%(RA), Rwp=7.98%, S=1.84, RBragg=4.30%(RCF). The occupancies of Ba and Bi in site 2b were refined but constrained to have their summation equal to 1.00. The same constraints were applied to the Ba and Bi of the 4e site. The results show that on site 2b there are 70% of Ba and 30% of Bi and on the site 4e there are 82% of Bi and 18% of Ba. The charge equilibrium is maintained for one standard deviation of the site occupancies.© 2000 International Centre for Diffraction Data.

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Type
New Diffraction Data
Information
Powder Diffraction , Volume 15 , Issue 2 , June 2000 , pp. 134 - 138
Copyright
Copyright © Cambridge University Press 2000

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References

Altomare, A., Burla, M. C., Camalli, M., Carrozzini, B., Cascarano, G., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G., and Rizzi, R. EXPO (Release 1.01) A suite of programs for powder Data: Extra + Sirpow.97. (1997). http://www.ba.cnr.it/IRMEC/SirWare.html.Google Scholar
Aurivillius, B. (1949). “Mixed Bi oxides with layer lattices. I. The structure type of CaNb 2Bi 2O 9,”Ark. Kemi 1, 463–480.Google Scholar
Blake, S. M., Falconer, M. J., McCreedy, M., and Lightfoot, P. (1997). “Cation disorder in ferroelectric Aurivillius phases of the type Bi2Anb209(A=Ba, Sr, Ca),”J. Mater. Chem. 7, 1609–1613.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
Foschini, C. R., Joshi, P. C., Varela, J. A., and Desu, S. B. (1999). “Properties of BaBi 2Ta 2O 9(BBT) thin films prepared by chemical solution deposition technique for DRAM applications,” J. Mater. Res. 14, 1860–1864.CrossRefGoogle Scholar
Ismundr, Kennedy, B. J., Gunawan, and Marsongkohadi, (1996). “Structure of ABi 2Nb 2O 9(A=Sr, Ba): Refinement of powder neutron diffraction data,” J. Solid State Chem. 126, 135–141.CrossRefGoogle Scholar
Lu, C. H., and Fang, B. K. (1998). “Synthesis processes and sintering behavior of layered-perovskite barium bismuth tantalate ceramics,” J. Mater. Res. 8, 2262–2268.Google Scholar
Marciniak, H. (1997). DMPLOT—Plot View Program for Rietveld Refinement Method. Version 3.48 Oct 1997. e-mail marcin@waw.unipress.pl.Google Scholar
Pechini, M. P. (1967). “Method of preparing lead and alkaline-earth titanates and niobates and coating method using the same to form a capacitor,” U.S. PATENT n °3 330 697, 11 July 1967.Google Scholar
Rae, A. D., Thompson, J. G., and Winthers, R. L. (1992). “Structure refinement of commensurately modulated bismuth strontium tantalate, Bi 2SrTa 2O 9,”Acta Crystallogr., Sect. B: Struct. Sci. 48, 418–428.CrossRefGoogle Scholar
Rae, A. D., Thompson, J. G., Winthers, R. L., and Willis, A. C. (1990). “Structure refinement of commensurately modulated bismuth titanate, Bi 4Ti 3O 12,”Acta Crystallogr., Sect. B: Struct. Sci. 46, 474–487.CrossRefGoogle Scholar
Riello, P., Canton, P., and Fagherazzi, G. (1995). “A semi-empirical asymmetry function for diffraction peak profiles,” Powder Diffr. 10, 204–206.CrossRefGoogle Scholar
Smolensky, G. A., Isupov, V. A., and Agranovskaya, A. I. (1961). “Ferroelectrics of the oxygen-octahedral type with layered structure,” Sov. Phys. Solid State 3, 651–655.Google Scholar
Srikanth, V., Idink, H., White, W. B., Subbarao, E. C., Rajagopal, H., and Sequeira, A. (1996). “Cation disorder in ferroelectric PbBi 2Nb 2O 9,”Acta Crystallogr., Sect. B: Struct. Sci. 52, 432–439.CrossRefGoogle Scholar
Subarrao, E. C. (1962a). “A family of ferroelectric bismuth compounds,” J. Phys. Chem. Solids 23, 665–676.CrossRefGoogle Scholar
Subarrao, E. C. (1962b). “Crystal chemistry of mixed bismuth oxides with layer type structure,” J. Am. Ceram. Soc. 45, 166–169.CrossRefGoogle Scholar
Young, R. A., Larson, A. C., and Paiva-Santos, C. O. (1999). “User's Guide to Program DBWS-980a7 FOR Rietveld Analysis of X-ray and Neutron Powder Diffraction Patterns.” School of Physics, Georgia Institute of Technology. Atlanta, GA. May of 1999. Copyright R. A. Young.Google Scholar
Young, R. A., Sakthivel, A., Moss, T. S., and Paiva-Santos, C. O. (1995). “DBWS-9411, an upgrade of DBWS*.* programs for Rietveld refinement with PC and mainframe computers,” J. Appl. Crystallogr. 28, 366–367.CrossRefGoogle Scholar
Young, R. A., and Wiles, D. B. (1982). “Profile shape functions in Rietveld refinements,” J. Appl. Crystallogr. 15, 430–438.CrossRefGoogle Scholar