A novel square pyramidal high-spin nickel(II) complex involving the quinquedentate NNN′-tris[2-(2′-pyridyl)ethyl]ethylenediamine

Abstract

The complex cation in the compound [Ni(tpen)]-(ClO₄)₂, MeNO₂, where tpen denotes the quinquedentate ligand NNN′-tris[2-(2′-pyridyl)ethyl]ethylenediamine, has been found (from its electronic spectrum and in its crystal structure) to be five covalent with all five nitrogen atoms of the chelate molecule bonded to the nickel atom in a somewhat distorted square pyramidal configuration.