Isomorphic modification of calcium hydroxyapatite by strontium

Abstract

X-ray photoelectron spectroscopy studies changes in the electronic structure of calcium hydroxyapatite with partial or total isomorphous substitution of Ca for Sr is reported in the current work. It is established significant increase in the binding energy of the core levels for calcium, oxygen and phosphorus atoms, indicating electronic density loss from these atoms and increase of the covalent component in general balance of the chemical bond. Based on numerical calculations by the LMTO method it was concluded that indirect metal-metal interaction for strontium apatite in triangles of the metal atoms is less expressed.