The nature of dielectric thermostability of barium lantanoid tetratitanates

The problem of combining in barium lantanoid tetratitanates (BLT) polycrystalline compositions a high dielectric permittivity with its temperature independence and low microwave losses has been revealed. It is suggested that 4f/5d lantanoid bonds viscously suppress the interaction of large polarizable TiO6 octahedrons. This hypothesis has been verified by intensive electronic relaxation process with a low activation energy and by submillimeter waves absorption. Because of the last the microwave applications of BLT-compositions is bounded by frequency limit 3-5 GHz.