F+centre in (Ca-Sr) carbonated hydroxyapatites
- 1 January 1983
- journal article
- research article
- Published by Taylor & Francis in Radiation Effects
- Vol. 72 (1-4) , 299-302
- https://doi.org/10.1080/00337578308218657
Abstract
Powdered samples of synthetic carbonated hydroxyapatites with variable amounts of strontium substituting for calcium, obtained by precipitation, were studied by ESR at the X-band frequencies after heating at 400°C for 24 h, X-irradiation and annealing at 150°C for 30 min. The F+ centre spectrum exhibiting orthorhombic symmetry was recorded between RT and 120 K, with <g>≃2. When the amount of carbonate inside the samples increases, the spectral intensity has the same behaviour than that of the quantity of O2- vacancies calculated from results of chemical analysis. Our results are a confirmation of the existence of two different mechanisms of charge compensation when CO3 2- substitutes for PO4 3-, and they also show that Sr ions are not located in cation sites adjacent to carbonate ions.Keywords
This publication has 2 references indexed in Scilit:
- ESR of the F+ centre in b-type carbonated hydroxyapatitePhysica Status Solidi (a), 1981
- Résonance paramagnétique électronique du centre F+ dans les fluorapatites carbonatées de type BJournal of Solid State Chemistry, 1980