Crystal structure of nonstoichiometric copper-substituted La(Ni{sub 1{minus}z}Cu{sub z}){sub x} compounds studied by neutron and synchrotron anomalous powder diffraction
- CNRS, Thiais (France). Lab. de Chimie Metallurgique des Terres Rares
- Philips Research Labs., Eindhoven (Netherlands)
The structural properties of the potential battery electrode materials LaNi{sub 4}Cu, LaNi{sub 4.4}Cu, LaNi{sub 5}Cu, and LaNi{sub 4.5}Cu{sub 1.5} have been investigated by neutron and anomalous synchrotron powder diffraction. The nonstoichiometry of such AB{sub x} (5 {le} x {le} 6) compounds has been described in a structure derived from the hexagonal CaCu{sub 5}-type structure by replacement of the A atoms by dumbbells of B atoms. In these copper-substituted compounds, Cu can occupy any of the four available nickel sites. From a joint refinement procedure using both neutron and synchrotron data, the copper-to-nickel ratio at each B site has been determined. This shows that substitution is not random and that copper occupies some crystallographic sites preferentially. The results are discussed and compared to other substituted AB{sub 5} systems.
- OSTI ID:
- 696666
- Journal Information:
- Journal of Solid State Chemistry, Vol. 146, Issue 2; Other Information: PBD: Sep 1999
- Country of Publication:
- United States
- Language:
- English
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