Crystal and molecular structure of bistriphenyl(ethyl)phosphonium pentanitratocerium(III)

Abstract

Crystals of the title compound are monoclinic of space group C2/c with a= 19·83(3), b= 11·05(2), c= 21·76(3)Å, β= 108·17°, and Z= 4. The anion has crystallographic C₂ symmetry and the cerium atom is ten-co-ordinate, being chelated symmetrically by the five bidentate nitrate ligands. The mean Ce–O distance is 2·57(2)Å. The co-ordination geometry is not very readily described in terms of any idealised high co-ordination polyhedron, but if each nitrate ligand is considered, as occupying one co-ordination site, then the arrangement closely approximates to a trigonal bipyramid. The structure was solved from X-ray photographic data by Patterson and Fourier methods and refined by least-squares techniques to R 9·8% for 1516 observed reflections.