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In the present work, a series of scheelite-related ( Li0.5 Ln0.5) MoO4 ( Ln = Nd, Er, Gd, Y, Yb, Sm, and Ce) ceramics were prepared by using the solid-state reaction method. Except for the ( Li0.5 Yb0.5) MoO4, the other compositions were found to have a scheelite structure. Among all the compositions, the ( Li0.5 Sm0.5) MoO4, ( Li0.5 Nd0.5) MoO4, and ( Li0.5 Ce0.5) MoO4 ceramics were found to possess low sintering temperatures below melting point of aluminum (660°C) and be chemically compatible with Al. The relation between microwave dielectric properties and structure was analyzed by using the Shannon additive rule and bond-valence theory. This series of microwave dielectric ceramics might be candidate for low temperature co-fired ceramics technology. [ABSTRACT FROM AUTHOR]

Phase structure and dielectric behavior of Bi 3 (Nb 0.9 M 0.1 )O 7+δ ceramics (M = Ti, Zr, Sn, W, δ = ±0.05) were discussed. Cubic fluorite solid solutions Bi 3 (Nb 0.9 M 0.1 )O 7+δ (M = Zr, Sn, W, δ = ±0.05) were obtained through a conventional solid state reaction method. An analysis of the microwave dielectric properties showed that substitution of Nb 5+ by W 6+ was favorable to improving the temperature coefficient of resonant frequency (TCF value). A temperature stable dielectric material Bi 3 (Nb 0.9 W 0.1 )O 7.05 was introduced. The Bi 3 (Nb 0.9 W 0.1 )O 7.05 ceramics sintered at 930 °C for 2 h exhibited a high permittivity of 92.4, a Qf value of 260 GHz and a TCF value of −34 ppm/°C. [ABSTRACT FROM AUTHOR]