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Structure and Microwave Dielectric Properties in the x Ca2AlNbO6: (1-x) Ca3Nb2O8 System
Published
Author(s)
Julia Y. Chan, Terrell A. Vanderah, Robert S. Roth, Winnie Wong-Ng, B A. Reisner, Richard G. Geyer
Abstract
The structure and dielectric properties of bulk ceramics in the xCa2AlNbO6: (1-x)Ca3Nb2O8 system were studied. Ca2AlNbO6 (P21/n, a = 5.3785(1) , b = 5.4158(1) , c = 7.6259(1) , b = 89.93(1)o) is a double perovskite with structure similar to CaTiO3 and Ca3Nb2O8 is a defect perovskite-related phase (a = 23.803(1) ). The end members exhibit temperature coefficients of resonant frequency (Df) that are opposite in sign; therefore, compositions along the tie linebetween them were prepared to examine the dielectric properties. Materials in this system exhibit modest relative permittivities (24 < er < 39) and low dielectric loss (7000 < Q x f < 14000 at 6 GHz). At the composition near x = 0.6, the relative permittivity is 26 with Df near 0 ppm at 7 GHz. Synthesis, structural characterization from single-crystal X-ray and powder neutron diffraction, and the dielectric properties of the phases will be described.
Chan, J.
, Vanderah, T.
, Roth, R.
, Wong-Ng, W.
, Reisner, B.
and Geyer, R.
(2000),
Structure and Microwave Dielectric Properties in the x Ca<sub>2</sub>AlNbO<sub>6</sub>: (1-x) Ca<sub>3</sub>Nb<sub>2</sub>O<sub>8</sub> System, Sigma Xi Post Doctoral Poster Presentations, 2000, washington, DC, US
(Accessed October 14, 2025)