METAL-ION COMPOUNDS OF 2,2,4,10,10,12-HEXAMETHYL- 1,5,9,13-TETRA-AZACYCLOHEXANE (L). Olga Gladkikh*, Neil F. Curtis*, Graeme A. Gainsford** and David A. Rae***, *Victoria University of Wellington, Wellington, New Zealand, **Industrial Research Ltd, Gracefield, Wellington, New Zealand, ***Australian National University, Canberra, Australia

A series of new complexes of divalent Co, Ni and Cu with the macrocyclic ligand L have been synthesized and analysed by both experimental (X-ray single crystal analysis) and theoretical (molecular mechanics) methods.

Tetra-coodrinate coordination compounds of (L) with cobalt(II), nickel(II) and copper(II) have coordination geometries intermediate between tetrahedral and square planar. The extent of the twisting of the coordination plane increases from S = 0 nickel(II) through copper(II) to S = 4 Co(II), which is close to tetrahedral. It also varies significantly with the counter-ion for the perchlorate and tetrachlorozincate salts.