RECENT DEVELOPMENTS IN THE METALLOSUPRAMOLECULAR AND MOLECULAR-STRUCTURES OF THE COBALT, IRON AND VANADIUM COMPLEXES OF THE DIANIONIC TETRADENTATE SCHIFF-BASE LIGANDS OF SALICYLIDENEIMINE AND ACETYLACETONEIMINE

Four different types of metallosupramolecular structures are distingui shable for the title complexes. These types are described as: (a) The metal complex could react with other metal ions as a ligand, (b) Dimer ization occurs through Lewis acid and Lewis base interactions of the m etal ion and the coordinated oxygen atom of the ligand with those of a n adjacent molecule, (c) Dimerization and chain formation occur using the donor-acceptor behaviour of the oxovanadium (IV) ion, and (d) Mole cular association occurs through the bridged fluoride. Types (b), (c) and (d) are self-assembly. Chemical understanding of those types could lead to designing, and establishing procedures for, the preparation o f new metallosupramolecular structures of homo and heterobinuclear las well as polynuclear) metal complexes with similar or mixed ligands.