title: EXAFS study of structural disorder in carbonate-containing hydroxyapatites.
abstract: A structural characterization of pure hydroxyapatite and partially carbonated hydroxyapatites has been performed using EXAFS spectroscopy, X-ray diffraction, and infrared spectroscopy. Our findings show that marked structural changes within the hydroxyapatite unit cell accompany the substitution of the phosphate anion. Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy has shown that the incorporation of carbonate into the phosphate site alters the structural geometry beyond the nearest neighbor oxygen coordination to calcium in a manner consistent with an increase in structural disorder. The nearest neighbor coordination to calcium is not detectably affected by the presence of carbonate.
authors.affiliation: SERC Daresbury Laboratory, Warrington, UK.
authors.forename: J E
authors.initials: JE
authors.lastname: Harries
authors.forename: S S
authors.initials: SS
authors.lastname: Hasnain
authors.forename: J S
authors.initials: JS
authors.lastname: Shah
mesh_terms: D017886:Durapatite; D006882:Hydroxyapatites / Q000032:analysis*; D013054:Spectrophotometry, Atomic; D013055:Spectrophotometry, Infrared; D014961:X-Ray Diffraction
chemical_list: D006882:Hydroxyapatites; D017886:Durapatite