Microwave dielectric properties and Raman spectroscopy of Scheelite solid solution [(Li_0.5Bi_0.5)_1-xCa_x] MoO₄ ceramics with ultra-low sintering temperatures

A Scheelite solid solution was formed based on [(Li_0.5Bi _0.5)_1-xCa_x]MoO₄ ceramics and prepared via a solid state reaction method in the range 0.0 ≤ x ≤ 1.0. High performance microwave dielectric properties were obtained in the [(Li _0.5Bi_0.5)_0.15Ca_0.85]MoO₄ ceramic sintered at 760°C with a relative permittivity of 14.1, a Qf value of 24,000 GHz (at 10.0 GHz), and a temperature coefficient value of +10.7 ppm/°C and the [(Li_0.5Bi_0.5)_0.1Ca _0.9]MoO₄ ceramic sintered at 850°C with a relative permittivity of 12.7, a Qf value of 41,300 GHz (at 10.3 GHz), and a temperature coefficient value of -16.5 ppm/°C. X-ray diffraction, Raman spectroscopy and the classical damped oscillator model were applied to study the relationship between the microwave dielectric properties and structures.