Synthesis and distribution of cations in substituted lead phosphate lacunar apatites

Journal Article · Thu Feb 15 04:00:00 EST 2007 · Materials Research Bulletin

DOI:https://doi.org/10.1016/j.materresbull.2006.05.027· OSTI ID:21000591

Hamdi, Besma ^[1]; Feki, Hafed El ^[1]; Savariault, Jean-Michel ^[2]; Salah, Abdelhamid Ben ^[1]

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1. Laboratoire de Sciences des Materiaux et d'Environnement, Faculte des Sciences de SFAX, BP 802, 3018 SFAX (Tunisia)
2. Centre d'Elaboration de Materiaux et d'Etudes Structurales, 29 rue J. Marvig, BP 4347, 31055 Toulouse Cedex 4 (France) and Universite Paul SABATIER, 118 Route de Narbonne, 31400 Toulouse (France)

Synthesis of apatites, Pb{sub 7.4}Bi{sub 0.3}Na{sub 2.3}(PO{sub 4}){sub 6} (I), Pb{sub 7.36}Bi{sub 0.32}Na{sub 2.08}Li{sub 0.24}(PO{sub 4}){sub 6} (II) and Pb{sub 5.78}Bi{sub 0.81}Ca{sub 0.60}Na{sub 2.81}(PO{sub 4}){sub 6} (III), with anion vacancy were carried out during solid state reactions. The three compounds of apatite-type structure crystallize in the hexagonal system, space group P6{sub 3}/m. In every compound, a preferential occupation of the (6h) site by Pb and Bi cations is shown revealing the influence of their lone electronic pair. The introduction of calcium increases the quantity of bismuth in these apatites. Alkaline metals occupy mainly the (4f) site. Infrared spectroscopy is correlated to the bonding scheme. A connection between the cations occupying (4f) sites and the c cell parameters is presented.

• OSTI ID: 21000591
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 2 Vol. 42; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION SPECTROSCOPY
APATITES
BISMUTH
CALCIUM
CATIONS
CHEMICAL PREPARATION
DEFECTS
HEXAGONAL LATTICES
INFRARED SPECTRA
INORGANIC COMPOUNDS
LEAD PHOSPHATES
SPACE GROUPS
VACANCIES
X-RAY DIFFRACTION