Abstract
The crystal structure of the microwave dielectric ceramics Ba(Ca 1/3Nb 2/3)O 3 synthesized by the molten salt method has been refined, from X-ray diffraction, in a trigonal order–disorder lattice with the P 3 ¯ m 1 ( D 3 d 3 ) space group. The lattice distortion and cation ordering are attributed to the large Ca 2+ ions at B′-site, which induces a large deviation of bond valence sums of the B-site ions. The ordering degree determined by the variations of the occupancies of Ca and Nb ions is 0.44. High-resolution transmission electron microscopy (HRTEM) and Raman spectrum show the evidence in support of the 1:2 B-site order–disorder model. The complete Raman mode assignment for Ba(Ca 1/3Nb 2/3)O 3 with order–disorder structure is also presented.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
