From a homogeneous Ziegler-Natta catalyst, a polymerisation active single crystal of the title compound was isolated. The crystal is triclinic, space group, P1, with a 15.196(6), b 15.263(5), c 13.749(4) ? a 90.01(2), b 95.12(3), and g 82.65(3)? Z = 1. The final R = 0.087. Atomic coordinates are given. The coordination no. of Nd is 7, and the configuration of Nd is monocapped prism. The Nd atoms can be divided into 3 groups according to their coordination environment. All the Nd atoms are connected by m2-Cl and m3-Cl atoms into a mol. skeleton. The active center of the bimetallic complex responsible for diene polymerisation is also discussed.

Key words: CRYSTAL STRUCTURE DETERMINATION, X-RAY DIFFRACTION ANALYSIS, HOMOGENEOUS CATALYSIS, SINGLE CRYSTALS, NEODYMIUM COMPOUNDS, ALUMINIUM COMPOUNDS, POLYNUCLEAR COMPLEX, DUAL METAL REFORMING CATALYST, ZIEGLER-NATTA CATALYST