Microwave dielectric properties of novel lithium containing pyrochlore type oxides: Li3Sm3-xBixTi7Nb2O25 (x=0, 1, 2 or 3)

Abstract

Microwave dielectric properties of novel lithium ion containing pyrochlore type oxides: Li3Sm3-xBixTi7Nb2O25 (x=0, 1, 2 or 3) have been reported in this paper. Powder X-ray diffraction patterns show that these oxides have cubic pyrochlore type structure. Ceramic microstructure of the sintered samples show well formed grains. They have relatively high dielectric constant (epsilon(r)) in the range 80-137 at 1 MHz and epsilon(r), 45-83 at the resonant microwave frequency region. It is seen that the dielectric constant (epsilon(r)) increases with the increase of Bi content. The best microwave dielectric properties obtained for fully substituted samarium compound, Li3Sm3Ti7Nb2O25 are as follows: Q x f=2007 and epsilon(r)=45 at the resonant microwave frequency, 3.78 GHz