Hydroxyapatite with Substitution of Calcium Cations by Magnetic Iron Ions

The results of calculations of the calcium cations substitution by iron in hydroxyapatite lattice using density functional theory methods are presented. Changes in the unit cell parameters and unit cell volume, the energy bands, and the magnetic properties with increasing number of substitutions in different calcium positions and for various charge of iron ions were analyzed in comparison with experimental data. The arisen magnetic properties of Fe-HAP are proportional to the amount of Fe introduced and energy levels Ei, filled by spin-up and spin-down electrons in different ratios.