Dielectric properties of TiO2-Nb2O crystallographic shear structures

The dielectric constants (K) have been measured near ambient temperature for polycrystalline bulk ceramics of the crystallographic shear compounds TiNb24O62, Ti2Nb10O29, and TiNb2O7. These show enhanced K's over Nb2O5 and TiO2, with the 2:10:29 phase displaying an ambient temperature K of approximately 130. We also report the effects of partial substitution of Nb by Ta. In general, thr dielectric constants are enhanced for 5-10% Ta substitution with the detailed behavior differing for the three phases.