微波介质陶瓷是5G时代信息功能陶瓷元器件应用关键材料，其微波频率下介电响应机理是本领域持续关注的基础性关键科学问题。大量研究表明陶瓷微波介电响应根源于离子晶体内部化学键特性，介电性能优化源于内部化学键调控。本项目基于复杂晶体化学键理论，以三方晶系Ln2Zr3(MoO4)9体系为研究对象，通过实施A位/B位离子掺杂建立模型探索化学键调控机理，深入研究结构中化学键特性与微波介电性能之间的内在联系；以化学键键能、键价特性、晶格能等关键参数为切入点，将其与复杂晶体中传统的结构/化学键表征模型有机地联系起来，从而提供一种揭示化学键本质-晶体结构-介电性能相互关系的方法，揭示材料的结构特征和介电性能调控的物理机制，从而达到优化材料微波介电性能的目的；同时，该研究成果可以推广至其它材料体系，实现从组分与结构到介电性能的预测和新材料体系的设计，为进一步理解微波介电响应根源提供理论基础。

Microwave dielectric ceramics are one of the key materials for information functional ceramic components in 5G period, and the dielectric response at microwave frequency has been the fundamental scientific issue in this field. Much research has shown that the microwave dielectric response of ceramic is closely related to the internal chemical bond characteristics of ionic crystals, and the optimization of dielectric properties is originated from regulation of internal chemical bond. Based on the chemical bond theory, the novel hexagonal Ln2Zr3(MoO4)9 system is chosen as research object，and the physical model is built to explore the intrinsic relationship between chemical bond properties and microwave dielectric properties by performing the modulation of A-site ion and the doping of B-site ion. According to the quantitative calculation of chemical bonds, the key parameters such as chemical bond energy, bond valence characteristics and lattice energy are adopted to investigate to the association between traditional structural/chemical bond characterization models in complex crystals. Thus a method will be explored to resolve the relationship among chemical bond nature, crystal structure and microwave dielectric properties. The structural characteristics and the physical mechanism of microwave dielectric properties can be revealed, which achieve the purpose of optimizing dielectric properties of materials. At the same time, these findings can be used to realize the prediction on composition-structure-dielectric properties and the design of new material systems, which provide a theoretical basis for further understanding the source of microwave dielectric response.