Hostname: page-component-6bf8c574d5-b4m5d Total loading time: 0 Render date: 2025-02-22T16:55:29.701Z Has data issue: false hasContentIssue false
  • English
  • Français

Formation and Characterization of “1:1” Ordered Phases in Am4+O3 - A(B2+1/3Ta2/3)O3 (A= Ba, Sr; B2+ = Mg, Zn; M4+ = Ti, Sn, Zr, Ce) Perovskites

Published online by Cambridge University Press:  15 February 2011

L. Chai ,
M. A. Akbas  and
P. K. Davies
L. Chai
Affiliation:
Department of Materials Science & Engineering, University of Pennsylvania, Philadelphia, PA, 19104–6272, lchai(or akbas, davies@lrsm.upenn.edu
M. A. Akbas
Affiliation:
Department of Materials Science & Engineering, University of Pennsylvania, Philadelphia, PA, 19104–6272, lchai(or akbas, davies@lrsm.upenn.edu
P. K. Davies
Affiliation:
Department of Materials Science & Engineering, University of Pennsylvania, Philadelphia, PA, 19104–6272, lchai(or akbas, davies@lrsm.upenn.edu
Get access

Abstract

Previous research has demonstrated that the formation of nano-sized “1:1” cation ordered domains in Zr4+ substituted Ba(Zn1/3Ta2/3)O3 may be responsible for the anomalies in the dielectric loss properties of these perovskite ceramics. To explore the structure and crystal chemistry of these phases, the effect of a series of M4+ substitutions (Zr4+, Ce4+, Sn4+, and Ti4+) on the B-site cation ordering in Ba(Zn1/3Ta2/3)O3, Ba(Mg1/3Ta2/3)O3, and Sr(Mg1/3Ta2/3)O3 has been examined. In all cases the substitution of low levels (∼ 5 mole %) of “over-sized” tetravalent cations (e.g. Zr4+, Ce4+) promotes a transformation to a 1:1 ordered phase, while the introduction of “under-sized” cations (e.g. Ti4+) stabilizes a disordered perovskite. Using Rietveld methods the structures of the 1:1 ordered A(βI1/2βII1/2)O3 phases were found to conform to a “random layer” model in which the βII positions are occupied by Ta, and the βI sites by a random distribution of the Mg(Zn), M4+ and residual Ta cations.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 453: Symposium R – Solid State Chemistry of Inorganic Materials , 1996 , 443
Copyright
Copyright © Materials Research Society 1997

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

REFERENCES

1. Negas, T., Yeager, G., Bell, S. and Amren, R., in Chemistry of Electronic Ceramic Materials, edited by Davies, P.K. and Roth, R.S., (NIST Special Publication 804, 1991), p. 21–37.Google Scholar
2. Davies, P. K., in Materials and Processing for Wireless Communication, edited by Negas, T. and Ling, H., (Am. Ceram. Soc., Westerville, OH, 1994), p. 137–152.Google Scholar
3. Galasso, F., Perovskites and High Tc Superconductors, Gordon and Breach Science, New York, 1990.Google Scholar
4. Jacobson, A. J., Collins, B.M., and Fender, B.E.F., Acta Cryst., B32, 1083 (1976).Google Scholar
5. Vincent, H., Perder, Ch., Theririer, Ph., and Labeyrei, M., Mat. Res. Bull. 28, 951 (1993).Google Scholar
6. Kawashima, S., Nishida, M., Ueda, I., and Ouchi, H., J. Am. Ceram. Soc, 66, 421 (1983).Google Scholar
7. Matsumoto, K., Hiuga, T., Takada, K., and Ichimura, H., in Proceedings of the 6th IEEE International Symposium on Application of Ferroelectrics, (Institute of Electrical and Electronic Engineers, New York, 1986), p. 118–121.Google Scholar
8. Tamura, H., Konoike, T, Sakabe, Y., and Wakino, K., J. Am. Ceram. Soc, 67, C–59 (1984).Google Scholar
9. Davies, P. K., Tong, J., and Negas, T., J. Am. Ceram. Soc., (1996, submitted).Google Scholar
10. Larson, A.C. and Von Dreele, R.B., Los Alamos Laboratory Report No. LAUR-86–748.Google Scholar
11. Izumi, F., in The Rietveld Method, edited by Young, R.A., Oxford University Press, Oxford, 1993, p. 111.Google Scholar