Mg{sub 8}Rh{sub 4}B - A new type of boron stabilized Ti{sub 2}Ni structure
- Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 01187 Dresden (Germany) and Department of Chemistry, Moscow State University, Moscow 119992 (Russian Federation)
- Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 01187 Dresden (Germany)
- EMAT, University of Antwerp, Antwerp B-2020 (Belgium)
- Department of Chemistry, Moscow State University, Moscow 119992 (Russian Federation)
The new magnesium rhodium boron compound Mg{sub 8}Rh{sub 4}B has been synthesized by reaction of the metal powders with crystalline or amorphous boron or the RhB precursor. The crystal structure of Mg{sub 8}Rh{sub 4}B was solved using single-crystal X-ray diffraction data (space group Fd3-bar m, a=12.1711(4)A, Z=8, 174 reflections, R{sub F}=0.016). The crystal structure can be described as a filled Ti{sub 2}Ni type where the interstitial sites 8b (12,12,12), located at the center of two nested Mg{sub 4}Rh{sub 4} tetrahedra, are occupied by boron atoms. Taking into account the absence of the Ti{sub 2}Ni-type phase in the binary Mg-Rh system, the boron atoms can be considered as stabilizing this structural motif. From the bonding analysis with the electron localization function the crystal structure is described as covalently bonded [Rh{sub 4}B]{sup 3-} anions, embedded in a cationic magnesium matrix.
- OSTI ID:
- 20905434
- Journal Information:
- Journal of Solid State Chemistry, Vol. 179, Issue 9; Conference: 15. international symposium on boron, borides and related compounds, Hamburg (Germany), 21-26 Aug 2005; Other Information: DOI: 10.1016/j.jssc.2005.11.029; PII: S0022-4596(05)00571-2; Copyright (c) 2005 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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