Predicted energies and structures of {beta}-Ca{sub 3}(PO{sub 4}){sub 2}
- Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom)
- Materials Science Department, AWE, Aldermaston, Berkshire RG7 4PR (United Kingdom)
One of the 6a cation sites of the {beta}-Ca{sub 3}(PO{sub 4}){sub 2} structure has previously been described as half occupied. Here, classical static lattice techniques are used to model the different configurations that the Ca ions can exhibit over these Ca(4) 6a sites. All possible configurations in the single primitive unit cell and a hexagonal supercell 3{sub h}x1x1 have been generated, along with configurationally averaged structures, that exhibit the experimentally reported R 3c symmetry. The lowest energy configuration of the primitive cell exhibits R 3 symmetry. Conversely, the lowest energy configurations derived from the hexagonal supercell, which are considerably more stable, exhibit P 3{sub 1} and P 3{sub 2} symmetries, which are isomorphic supergroups of R 3c. The implication of these simulations are discussed in terms of refined structural models of the material. - Graphical Abstract: One of the 6a cation sites of the {beta}-Ca{sub 3}(PO{sub 4}){sub 2} structure has previously been described as half occupied. Here, classical static lattice techniques are used to model the different configurations that the Ca ions can exhibit over these Ca(4) 6a sites. All possible configurations in the single primitive unit cell and a hexagonal supercell (3{sub h}x1x1) have been generated, along with configurationally averaged structures, that exhibits experimentally reported R 3c symmetry. The lowest energy configuration of the primitive cell exhibits R 3 symmetry. Conversely, the lowest energy configurations derived from the hexagonal supercell cell, which are considerably more stable, exhibit P 3{sub 1} and P 3{sub 2} symmetries, which are isomorphic supergroups of R 3c. The implication of these simulations are discussed in terms of refined structural models of the material.
- OSTI ID:
- 21484504
- Journal Information:
- Journal of Solid State Chemistry, Vol. 183, Issue 10; Other Information: DOI: 10.1016/j.jssc.2010.08.008; PII: S0022-4596(10)00342-7; Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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