부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.materresbull.2007.02.031 Byline: I. Mayer (a), S. Cohen (a), S. Gdalya (a), O. Burghaus (b), D. Reinen (b) Keywords: A. Inorganic compounds; D. Crystal structure; D. Electronic paramagnetic resonance (EPR) Abstract: Mn-doped [beta]-tricalcium phosphate was prepared by solid state reaction at 1100[degrees]C. The crystal structure of Ca.sub.2.85Mn.sub.0.15(PO.sub.4).sub.2, was determined by single crystal X-ray diffraction and found to be rhombohedral, R3c. Unit cell parameters are: a =10.3419(3); c =37.025(3)A (hexagonal setting), Z =21. Structure refinement data show that from the five Ca positions the Ca(4) site is only half filled and that the Mn.sup.2+ ions occupy the hexacoordinated Ca(5) site solely. EPR spectroscopy reveals that manganese in solid solutions Ca.sub.3-x Mn.sub.x (PO.sub.4).sub.2 (x =0.1; 0.28; 0.6) is divalent and supports the structure refinement results that Mn occupies the Ca(5) site with a geometry very near to a regular octahedron. Author Affiliation: (a) Department of Inorganic and Analytical Chemistry, Hebrew University, Jerusalem 91904, Israel (b) Fachbereich Chemie and Zentrum fur Materialwissenschaften, Philipps Universitat, 35032 Marburg, Germany Article History: Received 4 September 2006; Revised 27 December 2006; Accepted 19 February 2007