Synthèse, affinement structural et étude spectroscopique par IR et RMN-MAS des hydroxyapatites mixtes calcium-zinc
Written by sctunisie no commentsSolid solutions of calcium and zinc hydroxyapatite [Ca(10-x)Znx(PO4)6(OH)2] were synthesized by a wet process in a basic medium. They were investigated by X-ray diffraction, chemical analysis, IR and 31P NMR-MAS spectroscopies. The powder X-ray diffraction patterns of the solid products reveal that apatite can be obtained as a unique crystalline phase only for zinc concentration in solution up to 20 atoms percent. Solid state 31P NMR-MAS spectroscopy supposes that zinc atoms are statistically distributed between the two non-equivalent crystallographic sites. IR spectra show the presence of characteristic absorption bands for the apatitic structure and the splitting of the band ca. 340 cm-1 assigned to the “ν3” type stretching of the [M(II)3–OH] owing to the presence of the zinc in the second crystallographic site S(II). Results of spectroscopic study by 31P NMR-MAS and IR were confirmed by the Rietveld structural refinement using Fullprof program.
T. Turki, A. Aissa, H. Agougui, M. Debbabi
Solid solutions, NMR-MAS spectroscopy, Crystallographic sites, Fullprof
Pages 161-172
