Structural Systematics of Rare Earth Complexes. XXI Polymeric Sodium Bis(thiodiglycolato)neodymiate(III)

Abstract

A single-crystal, room-temperature, X-ray structure determination is recorded for the title compound, NaNd(tdga)₂ (‘tdga^2-’ ≡ ⁻OCOCH₂SCH₂COO^-). Crystals are monoclinic, space group Pc, a 9·5058(4), b 7·323(1), c 9·402(4) Å, β 97·71(2)°, Z = 2 f.u., conventional R on |F| being 0·028 for N_o 1054 independent ‘observed’ (I > 3σ(I)) diffractometer reflections. The compound is a novel polymeric array; the neodymium atom is eight-coordinated by ligand oxygen atoms at distances ranging from 2·43(2) to 2·54(1) Å. A redetermination of the parent thiodiglycolic acid is also recorded (orthorhombic Pnam, a 5·0444(8), b 6·690(1), c 17·73(1) Å, Z = 4, R 0·038 for N_o 866).