ИСТИНА

Polar dielectric tricalcium phosphate, Ca3(PO4)2, is one of the main substances forming human bones and teethes. Much efforts are spending to make implants from Ca3(PO4)2 for medicine purposes. However until very recently nobody was interested in fundamental properties of this composition entering in one of the most plural structural family of phosphates, vanadates, arsenates, and closely related to minerals whitlockite and cerite. Most of members of family are active dielectrics possessing ionic conductive, ferroelectric or antiferroelectric, luminescent, and optical nonlinear properties. Separately, or in various combinations, these properties are widely required in engineering. We correlate outstanding characteristics of Ca3(PO4)2 and Ca3(VO4)2 derivatives with structural peculiarities responsible for the properties.