[EMAIL PROTECTED] schrieb:
> could somebody direct me to the structure of cubic lithium niobium oxide (Li3NbO4
>ao~8.4A); what is it isostructural with?
>
> L. Keller
Results of a short cross-check with the ICSD database:
Li3NbO4 is I-43m, cI64
K. Ukei et al. Acta Cryst C 50 (1994) 655.
an older entriy exists in I23 (J.C. Grenier, et al. Bull. Soc. Franc. Miner.
Cristallogr. 87 (1964) 316 are of identical
structure with too low symmetry, as discussed by Ukei et al)
The structure is a 2 x 2 x 2 NaCl superstructure (Nb1/4Li3/4)O (not mentioned by Ukei
et al), with tetrahedral "clusters" of
edge sharing NbO6 octahedra.
Li3TaO4 is different, I did not found other relatives.
Perhaps a crosscheck with reviews concerning NaCl-superstructures may help, e.g.
Glenn C. Mather, Christian Dussarrat, Jean Etourneau, Anthony R. West, A review of
cation-ordered rock salt superstructure
oxides, J. Mater. Chem. 10 (2000) 2219.
Andreas Leineweber
MPI fuer Metallforschung
Seestrasse 92
Stuttgart/Germany
