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Synchrotron X-ray Diffraction Study of Ba4.5Nd9Ti18O54 Microwave Dielectric Ceramics at 10–295 K

Published online by Cambridge University Press:  31 January 2011

C. C. Tang
Affiliation:
Daresbury Laboratory, Warrington, Cheshire WA4 4AD, United Kingdom
M. A. Roberts
Affiliation:
Daresbury Laboratory, Warrington, Cheshire WA4 4AD, United Kingdom
F. Azough
Affiliation:
Manchester Materials Science Centre, University of Manchester and UMIST, Manchester M1 7HS, United Kingdom
C. Leach
Affiliation:
Manchester Materials Science Centre, University of Manchester and UMIST, Manchester M1 7HS, United Kingdom
R. Freer
Affiliation:
Manchester Materials Science Centre, University of Manchester and UMIST, Manchester M1 7HS, United Kingdom
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Abstract

The structure of ceramic Ba4.5Nd9Ti18O54 was investigated by synchrotron x-ray powder diffraction from 10 to 295 K. Reitveld refinement and Le Bail profile analysis were applied to the data. Based on an orthorhombic structure, unit cell parameters of a = 22.3479(3) Å, b = 7.6955(1) Å, and c = 12.2021(2) Å were obtained at room temperature and a = 22.3367(5) Å, b = 7.6738(1) Å, and c = 12.1842(3) Å at 10 K. No evidence was found for any major structural change from 10 to 295 K. Within the tungsten bronze framework the two pentagonal channels were fully occupied by Ba; the remaining Ba atoms shared the rhombic channels with Nd. Thermal expansion of the unit cell was found to be anisotropic. The largest expansion occurs along the b cell edge, and the least along the a cell edge. It is proposed that the anisotropy is due to enhanced bending of the TiO6 polyhedra chains along the b direction.

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Articles
Copyright
Copyright © Materials Research Society 2002

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References

Kolar, D., Gaberšček, S., Stadler, Z., and Suvorov, D., Ferroelectrics 27, 269 (1980).CrossRefGoogle Scholar
Wakino, K., Minai, K., and Tamura, H., J. Am. Ceram. Soc. 67, 278 (1984).CrossRefGoogle Scholar
Matveeva, R.G., Varfolomeev, M.B., and Il’yushchenko, L.S., Russ. J. Inorg. Chem. (Engl. Trans.) 29, 17 (1984).Google Scholar
Ohsato, H., Ohhashi, T., Nishigaki, S., Okuda, T., Sumiya, K., and Suzuki, S., Jpn. J. Appl. Phys. 32, 4323 (1993).CrossRefGoogle Scholar
Ohsato, H., Ohhashi, T., Kato, H., Nishigaki, S., and Okuda, T., Jpn. J. Appl. Phys. 34, 187 (1995).CrossRefGoogle Scholar
Ubic, R., Reaney, I.M., and Lee, W.E., International Materials Reviews 43, 205 (1998).CrossRefGoogle Scholar
Rawn, C.J., Birnie, D.P. III, Bruck, M.A., Enemark, J.H., and Roth, R.S., J. Mater. Res. 13, 187 (1998).CrossRefGoogle Scholar
Okudera, H., Nakamura, H., Toraya, H., and Ohsato, H., J. Solid State Chem. 142, 336 (1999).CrossRefGoogle Scholar
Azough, F., Champness, P.E., and Freer, R., J. Appl. Crystallogr. 28, 577 (1995).CrossRefGoogle Scholar
Setasuwon, P., Freer, R., Azough, F., and Leach, C., in Millimeter/Submillimeter-Wave Technology Materials, Devices, and Diagnostics, edited by Sundaram, S.K., Woskov, P.P., Ogita, Y-I., and Tuovinen, J. (Mater. Res. Soc. Symp. Proc. 631, AA.2.7, 2000), available from http://www.mrs.org/publications/epubs/proceedings/spring2000/aa/Google Scholar
Silva, A., Azough, F., Freer, R., and Leach, C., J. Eur. Ceram. Soc. 20, 2727 (2000).CrossRefGoogle Scholar
Azough, F., Wright, A.C., and Freer, R., J. Mater. Sci. 36, 5093 (2001).CrossRefGoogle Scholar
Munro, I.H., J. Synchrotron Rad. 4, 344 (1997).CrossRefGoogle Scholar
Cernik, R.J., Murray, P.K., Pattison, P., and Fitch, A.N., J. Appl. Crystallogr. 23, 292 (1990).CrossRefGoogle Scholar
Collins, S.P., Cernik, R.J., Pattison, P., Bell, A.M.T., and Fitch, A.N, Rev. Sci. Instrum. 63, 1013 (1992).CrossRefGoogle Scholar
MacLean, E.J., Millington, H.F.F., Neild, A.A., and Tang, C.C., Mater. Sci. Forum 321–324, 212 (2000).CrossRefGoogle Scholar
Tang, C.C., G. Bushnell-Wye, and Cernik, R.J., J. Synchrotron Rad. 5, 929 (1998).CrossRefGoogle Scholar
Roberts, M.A. and Tang, C.C., J. Synchrotron Rad. 5, 1270 (1998).CrossRefGoogle Scholar
Hart, M. and Parrish, W., Mater. Sci. Forum 9, 39 (1986).CrossRefGoogle Scholar
Parrish, W., Hart, M., Erickson, C.G., Masciocchi, N., and Huang, T.C., Adv. X-ray Anal. 29, 243 (1986).Google Scholar
Rietveld, H.M., Acta Cryst. 22, 151 (1967).CrossRefGoogle Scholar
Rietveld, H.M., J. Appl. Cryst. 2, 65 (1969).CrossRefGoogle Scholar
Bail, A. Le, in Accuracy in Powder Diffraction II, NIST Spec. Pub. No. 846, edited by Prince, E. and Stalick, J.K. (U.S. Department of Commerce, Gaithersburg, MD, 1992), p. 213.Google Scholar
International Table for X-ray Crystallography, 4th ed., Vol. A, Space-Group Symmetry, edited by Hahn, Theo (Kluwer Academic Publishers, Dordrecht/Boston/London, 1995), p. 288.Google Scholar
International Table for X-ray Crystallography, 2nd ed., Vol. C, Mathematical, Physical and Chemical Tables, edited by Wilson, A.J.C. and Prince, E. (Kluwer Academic Publishers, Dordrecht/Boston/London, 1999), p. 572573.Google Scholar
Sasaki, S., KEK Report 88-14 (High Energy Accelerator Research Organization, Tsukuba, Japan, 1989).Google Scholar
Ohhashi, T., Thesis, M.S., Nagoya Institute of Technology, Japan (1994).Google Scholar