| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 175375 | Dyes and Pigments | 2016 | 5 Pages |
•New colored copper-doped apatite-type materials were synthesized.•Positions of the La and Cu ions in the crystal lattice were determined.•Relationships between crystal structure and spectral characteristics were described.•Specific chromophore centres were characterized.
Copper-containing Ca-La hydroxyapatites (HAPs) with chemical compositions Ca10-xLax(PO4)6O2H1.5-x-y-δCuy (x = 0–1.79; y = 0–0.57) were synthesized by solid state reaction. Structural parameters and atomic positions were refined using the Rietveld method in space group P63/m. It was found that La3+ ions occupied the Ca(2) position only and copper ions were located mainly inside the hexagonal channel. In contrast to known red-violet copper-doped Ca-apatites, the copper-doped Ca-La apatites exhibited lighter colors varying from pink to pale yellow and blue-grey tints. Chromophores in the compounds were characterized by diffuse reflectance spectroscopy, colorimetry, and resonant Raman spectroscopy.
