The crystal structure of tetraethylenglycoltrinitrato lanthanum(III): an example of undecacoordination

Abstract

The title compound has been prepared by reacting La(NO 3) 3 with tetraethylenglycol. The structure was determined from counter-collected data and refined to R = 0.049 for 2310 reflections. The space group is P2 1/n, monoclinic, with cell dimensions a = 12.75(1), b = 16.84(1), c = 8.15(1) Å, β = 101.27(3)°, D x = 2.01 g cm −3 for Z = 4. The pentadentate organic ligand wraps around the metal ion which is also bound to three chelate nitrato groups, thus achieving the rather uncommon undeca-coordination. Five La-O(nitrate) (mean 2.61 Å) compare well with the two LaO(alcohol) bond distances (mean 2.58 Å). One LaO (nitrate) (2.79 Å) and the three LaO(ether) bond distances (mean 2.70 Å) are significantly longer. Weak intra- and intermolecular hydrogen bonds are also present.