ISSN:
1551-2916
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
This work investigates the structure and stability of the pyrochlore solid solution PbnNb2O5+n using a combination of high-resolution electron microscopy and electron diffraction. The microwave dielectric properties of the series 1.5 ≤n≤3.0 have been established, and the effect of the substitution of Ta5+ for Nb5+ on dielectric properties has also been investigated for n= 1.5 and 2.0. Single-phase cubic pyrochlore was obtained for n= 1.5. Compositions for which n 〉 1.5 showed discreet PbO-rich layers on {111}cubic planes between alternating slabs of pyrochlore, similar in appearance to Ruddlesden–Popper phases. The occurrence of these layers results in a lowering of the overall symmetry to trigonal, and their presence was found to have a profound effect on the microwave dielectric properties.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1151-2916.2002.tb00483.x
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