Preparation and Structure Refinement of Monoclinic Hydroxyapatite

✍ Scribed by Toshiyuki Ikoma; Atsushi Yamazaki; Satoshi Nakamura; Masaru Akao

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 199 KB
• Volume: 144
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1998.8120

✦ Synopsis

Monoclinic hydroxyapatite was synthesized by a wet method followed by heating in air at 1473 K for 1 h. The product is carbonate-free and has a Ca/P ratio of 1.65, which is slightly lower than the theoretical value (1.67) of hydroxyapatite. The crystal structure was investigated by Rietveld re5nement using X-ray powder di4raction data. The structure has monoclinic symmetry with the space group P2 1 /b (No. 14), Z:4, Dx:3.14 g cm\ 3 , and the lattice constants are a:9.426(3) A s , b:18.856(5) A s , c:6.887(1) A s , and :119.97(1)3. The hydroxyl ions have an ordered arrangement along the hydroxyl columns. The hydroxyapatite prepared in the present study is 98% monoclinic.