Computational study of cation substitutions in apatites
- Department of Chemistry, Tallinn University of Technology, Ehitajate tee 5, EE-19086 Tallinn (Estonia)
- Laboratory of Inorganic Materials, Tallinn University of Technology, Ehitajate tee 5, EE-19086 Tallinn (Estonia)
Density-functional theory plane-wave modeling of fluor- and hydroxyapatites has been performed, where one or two calcium ions per unit cell were replaced with cadmium or zinc cations. It was found that cadmium ions favor Ca(1) positions in fluorapatites and Ca(2) positions in hydroxyapatites, in agreement with experiment. A similar pattern is predicted for zinc substitutions. In the doubly substituted cases, where only hydroxyapatites were modeled, a preference for the substituting ions to be located in Ca(2) position was also observed. Displacement of the hydroxide ions from their symmetrical positions on the hexagonal axis can be used to explain the preferred configurations of substituting ions around the axis. -- Deformation of the hydroxide ion chain due to substitutions around the ion channel in substituted hydroxyapatites.
- OSTI ID:
- 20785026
- Journal Information:
- Journal of Solid State Chemistry, Vol. 179, Issue 5; Other Information: DOI: 10.1016/j.jssc.2006.02.012; PII: S0022-4596(06)00105-8; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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