Five-co-ordination in nickel(II) complexes. Crystal structure of the high-spin complex of nickel(II) perchlorate with NN-bis-(2-diethylaminoethyl)-2-hydroxyethylamine

Abstract

The structure of the complex obtained by the reaction of the tripod-like ligand NN-Bis-(2-diethylaminoethyl)-2-hydroxyethylamine [Et₂N·CH₂·CH₂]₂N·CH₂·CH₂·OH (bdhe) with nickel(II) perchlorate has been determined by X-ray analysis. The crystals are orthorhombic, space group Pbca with Z= 4 in a unit cell of dimensions: a= 15·772 ± 0·020, b= 19·281 ± 0·016, c= 12·396 ± 0·008 Å. The structure has been solved by the heavy atom technique and refined to R 0·082 over 1177 independent observed reflections.

The structure consists of cationic dimers possessing a centre of symmetry. These dimers are formed by two ligand oxygen atoms bridging the nickel atoms, Ni ⋯ Ni′ distance 3·09 Å. The nickel atoms are five-co-ordinate, linked to three nitrogen and two oxygen atoms. Two perchlorate ions act as counter-ions.