Abstract
The ferroelectric lead germanate (Pb5Ge3O11) and its isomorphous compounds are important because of their uses as pyroelectric and electro-optic devices. Comparison of inter-planar d-spacings of Pb5Ge3−x Si x O11 (x=0, 0.3, 0.7 and 1.00) suggests that there is no change in basic structure of Pb5Ge3−x Si x O11 when Si is substituted for Ge in small quantity (x<1). The dielectric properties of the Si-substituted compounds have been studied as a function of temperature (30 to 200°C). The ferroelectric-paraelectric phase transition has been observed at 185°C. The Si doping causes (a) Curie point to shift towards low temperature, (b) peak value of the dielectric constant to decrease and (c) phase transition diffuse. The fast increase in dielectric constant of pure Pb5Ge3O11 with temperature (beyond transition temperature) may be attributed to the development of space charge polarization in the system.
Similar content being viewed by others
References
Eysel W, Wolfe R and Newnham R E 1973J. Am. Ceram. Soc. 56 185
Goto Y 1981J. Phys. Soc. Jpn. 50 538
Iwasaki H, Sugii K, Yamada T and Niizeki N 1971Appl. Phys. Lett. 18 444
Iwasaki H, Miyazawa S, Koizumi H, Sugii K and Niizekii N 1972J. Appl. Phys. 43 12
Lang S B 1974Source book of pyroelectricity, (New York: Gordon & Breach)
Lines M E and Glass A M 1977Principles and applications of ferroelectric and related materials. (Oxford: Clarendon Press)
Mansingh A, Srivastava K N and Singh B 1979J. Phys. Chem. Solids 40 9
Nanamatsu S, Iyama H Sug, Dol K and Kondo Y 1971J. Phys. Soc. Jpn. 31 616
Srinivasan M R 1984Bull. Mater. Sci. 6 319
Watton R, Smith C and Jones G R 1976Ferroelectrics.14 719
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Choudhary, R.N.P., Misra, N.K. & Chidambaram, P.S. Structural and dielectric properties of Pb5(Ge,Si)O11 . Pramana - J Phys 38, 347–353 (1992). https://doi.org/10.1007/BF02875381
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF02875381