Hostname: page-component-848d4c4894-p2v8j Total loading time: 0.001 Render date: 2024-05-16T01:08:02.031Z Has data issue: false hasContentIssue false

Crystal structures of (Ba1−xLax)[Mg(1+x)/3Nb(2−x)/3]O3 with 0.9 ≤ x ≤ 1.0

Published online by Cambridge University Press:  06 January 2012

Hyun Min Park
Affiliation:
New Materials Evaluation Center, Korea Research Institute of Standards and Science, Taeduk Science Town, P.O. Box 102, Taejon, 305–600, Korea
Hwack Joo Lee
Affiliation:
New Materials Evaluation Center, Korea Research Institute of Standards and Science, Taeduk Science Town, P.O. Box 102, Taejon, 305–600, Korea
Yang Koo Cho
Affiliation:
New Materials Evaluation Center, Korea Research Institute of Standards and Science, Taeduk Science Town, P.O. Box 102, Taejon, 305–600, Korea
Sahn Nahm
Affiliation:
Division of Materials and Metallurgical Engineering, Korea University, Seoul, 136–701, Korea
Get access

Abstract

Based on a structure model of mixture of phases, the crystal structure analysis of (Ba1−xLax)[Mg(1+x)/3Nb(2−x)/3]O3 (BLMN) (x = 0.9 and 1.0) by Rietveld refinements was carried out. The pure La(Mg2/3Nb1/3)O3 (LMN) and BLMN (x=0.9) actually consist of a two-phase mixture rather a single phase. One is Fm-3m, which is cubic and 1:1 ordered and the other is P21/n, which is monoclinic and has both 1:1 ordering and the antiphase and inphase tilting of oxygen octahedra with aac+. The weight fraction of the Fm-3m phase is 17.5% at x=0.9 and further decreases to 7.5% in pure LMN. Meanwhile, that of the P21/n phase is 82.5% at x =0.9 and further increases to 92.5% in pure LMN. The I4/m phase, which is present as a minor phase from x=0.3 to 0.7, disappeared when x≥0.9. The abrupt change of the x-ray diffraction pattern at x=0.9 is caused by a change of major phase from Fm-3m to P21/n phase in the matrix.

Type
Articles
Copyright
Copyright © Materials Research Society 2003

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

Negas, T., Yeager, G., Bell, S., and Armen, R., in Chemistry of Electronic Ceramic Materials, NIST Special Publication No. 804, edited by Davies, P.K. and Roth, R.S. (NIST, Washington, DC, 1991), pp. 2138.Google Scholar
Akbas, M.A. and Davies, P.K., J. Am. Ceram. Soc. 81, 2205 (1998).CrossRefGoogle Scholar
Lin, L.J. and Wu, T.B., J. Am. Ceram. Soc. 74, 1360 (1991).CrossRefGoogle Scholar
Kim, J.S., Cheon, C.I., Kang, H.J., Shim, H.S., Lee, C.H., Nahm, S., Byun, J.D., Mater. Lett. 38, 294 (1999).CrossRefGoogle Scholar
Glazer, A.M., Acta Crystallogr. B 28, 3384 (1972).CrossRefGoogle Scholar
Glazer, A.M., Acta Crystallogr. A 31, 756 (1975).CrossRefGoogle Scholar
Lee, H.J., Park, H.M., Cho, Y.K., Song, Y.W., Paik, J.H., Nahm, S., Byun, J.D., J. Am. Ceram. Soc. 83, 2875 (2000).CrossRefGoogle Scholar
Choi, I.K., Cho, B.J., Paik, J.H., Nahm, S., Kim, J.S., Lee, H.J., Park, H.M., Byun, J.D., Ahn, B.G., Mater. Res. Bull. 35, 921 (2000).CrossRefGoogle Scholar
Woodward, P.M., Acta Crystallogr. B 53, 32 (1997).CrossRefGoogle Scholar
Lee, H.J., Park, H.M., Cho, Y.K., Ryu, H., Paik, J.H., Nahm, S., Byun, J.D., J. Am. Ceram. Soc. 83, 937 (2000).CrossRefGoogle Scholar
Park, H.M., Lee, H.J., Cho, Y.K., Song, Y.W., Nahm, S., Byun, J.D., Mater. Res. Bull. 36, 2163 (2001).CrossRefGoogle Scholar
Rodriguez-Carvajal, FULLPROF, Program for the Rietveld Refinement (Institute Langavine, France, 1993).Google Scholar
Galasso, F. and Pyle, J., J. Phys. Chem. 67, 1561 (1963).CrossRefGoogle Scholar
Reaney, I.M., Colla, E.L., and Setter, N., Jpn. J. Appl. Phys. 33, 3984 (1990).CrossRefGoogle Scholar
Paik, J.H., Choi, C., Nahm, S., Byun, J.D., and Lee, H.J., J. Mater. Sci. Lett. 18, 889 (1999).CrossRefGoogle Scholar
Hirsch, P., Howie, A., Nicholson, R.B., and Whelan, M.J., Electron Microscopy of Thin Crystals (R.E. Kriger, New York, 1977), Ch. 5, p. 379.Google Scholar
Collar, E.L., Reaney, I.M., and Setter, N., J. Appl. Phys. 74, 3414 (1993).CrossRefGoogle Scholar
Levin, I., Bendersky, L.A., Cline, J.P., Roth, R.S., and Vanderah, T.A., J. Solid State Chem. 150, 43 (2000).CrossRefGoogle Scholar