Abstract
A detailed investigation of the polarized Raman spectrum of monoclinic hydroxyapatite (OHAp) and a careful study of the low frequency infrared spectrum of polycrystalline OHAp, is reported. Most of the spectral details of Raman scattering are consistent with the local pseudo-hexagonal C6 factor group symmetry of OHAp. However, some features, for example the absence of TO-LO splitting for particular E1 phonon geometries and the splitting of the lowest frequency Raman line, are a reflection of the centrosymmetric monoclinic lattice of OHAp. Between 0 and 50cm-1, a temperature-dependent background, having E1 symmetry, and probably associated with OH- disordering flucuations, was observed in OHAp. Both OHAp and FAp displayed low frequency Raman lines which softened with decreasing temperature. However, no evidence for a phase transition was found in either OHAp or FAp in the 12-295 K temperature range.
Original language | English (US) |
---|---|
Pages (from-to) | 923-927 |
Number of pages | 5 |
Journal | Journal of Physics and Chemistry of Solids |
Volume | 38 |
Issue number | 8 |
DOIs | |
State | Published - 1977 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- General Chemistry
- General Materials Science
- Condensed Matter Physics