Micro-Raman Line Broadening in Synthetic Carbonated Hydroxyapatite

Abstract
Using a Raman microspectrometer, we have recorded Raman spectra of synthetically produced hydroxyapatite samples with varying carbonate contents. The apatites were produced from aqueous solutions at about 40°C. From line-broadening values of the symmetric phosphate stretch, it was concluded that the carbonate substitution in these lattices has a maximum of 4.5 wt %. Both phosphate and hydroxyl ions seem to be involved in the carbonate substitution process.