Barium calcium hydroxyapatite solid solutions

Abstract

The replacement of calcium by barium in the hydroxyapatite structure by solid-state reaction at different temperatures and by precipitation from an aqueous system has been investigated by X-ray diffraction and i.r. absorption analyses. The products obtained by solid-state reaction at 1 200 °C are solid solutions over the range of barium concentration 60–100 atom %. The lattice dimensions and the i.r. frequencies of the solid solutions vary linearly with the atom % of barium. Only small amounts of barium can be incorporated in hydroxyapatite by precipitation from the aqueous system.