Molecular design of TB crystal material has made many new progress in recent years. Mainly reflected in that filling position A is applied to new elements; diversification and doping modification of filling position B element .

 

Some of the new crystals of molecules design and development by Foster is listed in Table 1. It can be found that the development of TB-type crystalline material, to fill the main position A traditionally with Ba, Sr, Pb, K and other elements entering, and the new trends of filling with La, Ce and other rare earth elements have appeared in recent years. There are rare reports about TB crystal material of earth elements in China, but there have been systematically studied in foreign countries. Position B is located by only a cationic occupied traditionally. In recent years, through the addition of low-valence cation in this position, the position A can be introduced more cations to balance electricity price, not only expanding the position A molecular design, but also being conducive to get stable crystal structure of TB.

 

Lightly doped TB crystal material, its performance can be improved to improve the quality of the crystal growth. Table following shows the properties changes of SBN, KNSBN after doping.

 

It is worth mentioned that progress of the application of TB-type crystal material is fast. SBN, PBN and other classic TB crystal materials, studies on of which preparation and properties of ceramic materials and film materials are active. Compared with the abroad, research on TB crystal materials with the W element used in position B is less in China. TB structure film of the phosphate has attracted great attention due to good prospects for superconducting applications, but the research in this aspect is weaker in China.