Structure, infrared spectra and microwave dielectric properties of the novel Eu2TiO5 ceramics

The microwave dielectric properties of Eu 2 TiO 5 ceramic prepared by a conventional solid-state method were investigated for the first time. An orthorhombic structure with Pnam space group was obtained from x-ray diffraction. On the basis of P-V-L chemical bond theory and refined lattice parameters, the bond parameters of bond ionicity, lattice energy, bond energy, and coefficient of thermal expansion of Eu 2 TiO 5 were computed. The relationship between chemical bond characteristics and microwave dielectric properties was discussed. Besides, far-infrared reflective spectra indicated the absorption of structural phonon oscillation might be the main contribution to polarization for Eu 2 TiO 5 ceramic. Eu 2 TiO 5 ceramic sintered at 1300°C for 6 hours possessed excellent microwave dielectric properties of ε r ~ 14.4 ± 0.2, Q × f ~ 21 000 ± 500 GHz, and τ f ~ −10 ± 2 ppm/°C.