Effect of chemical bonding and relative density on microwave dielectric properties of LiInW2O8 ceramics

To meet the demands of the growing field of electronic communications, LiInW 2 O 8 ceramics with low dielectric loss (high Q×f ) and low dielectric constant ( ε r ) are prepared by a solid phase reaction method. X-ray diffractometry reveals a scheelite single-phase structure for the prepared ceramics. Compared with the standard LiInW 2 O 8 , the as-prepared LiInW 2 O 8 has a higher relative diffraction intensity for the (200) crystal plane, indicating an anisotropic growth phenomenon in the present case. Raman spectroscopy and calculations of the P-V-L complex chemical bonding theory show that W-O bonding is a key factor affecting the dielectric properties of LiInW 2 O 8 ceramics. Furthermore, excellent microwave dielectric properties with ε r ≈ 14.2, Q×f ≈ 63000 GHz, and τ f ≈ −28 ppm/℃ are obtained by sintering the ceramic at 1025°C.