Usage of the P-V-L Bond Theory in Regulating Properties of Microwave Dielectric Ceramics

The rapid development of communication technology has put forward increasingly stringent requirements on dielectric ceramic filters.Efficient design of novel dielectric materials to facilitate their progression is of great significance.The relationship between structure and performance of materials is crucial for the synthesis and design of microwave dielectric ceramics.The P-V-L bond theory aims to provide crystal structure parameters and basic chemical bond characteristics through calculations, such as the bond ionicity, bond covalency, bond sensitivity, lattice energy, and bond energy.These parameters provide a theoretical basis and guidance formodification design of microwave dielectric ceramics.In recent years, researchers have been committed to applying the P-V-L bond theory to a large number of ceramic systems to explain the relationship between structure and performance of microwave dielectric ceramics.Based on this theory, new modification strategies have been proposed to obtain excellent microwave dielectric properties.This review provides a comprehensive overview of the fundamental concepts of the P-V-L bond theory and the binary bonding formula of complex polycrystals, and outlines the methods of calculating chemical bond parameters and chemical bond characteristics in the field of microwave dielectric ceramics.Meanwhile, the application of the P-V-L bond theory in several common microwave dielectric ceramic systems in recent years is analyzed.Data from literatures show that the P-V-L bond theory analysis can provide the bond characteristics in ion-doped modified systems, as well as the structural evolution and dielectric properties.This understanding is highly significant for guiding development and application direction of microwave dielectric ceramics.