The use of conductivity measurements in organic solvents for the characterisation of coordination compounds

Magnetochemistry: advances in theory and experimentation

The field of heteropolymetallic systems with magnetic metal centers occupies a crossing point between biology and physics. For instance the Cu(II)-Fe(III) interaction in cytochrome oxidase is of the same nature as the Cu(II)-Mn(II) interaction in a novel system which could be the first molecular ferromagnet. The mechanism of the interaction is discussed, both from a phenomenological view point using a spin Hamiltonian, and from an orbital view point. An orbital model for the isotropic interaction is presented. It is based on the concept of natural magnetic orbitals. The mechanism of the anisotropic and antisymmetric interactions is more briefly treated. The role of the Zeeman perturbation is then considered in relation with the magnetic and EPR properties of the heterobimetallic complexes. Several examples are presented to emphasize that the nature, ferro- or antiferromagnetic of the isotropic interaction is controlled by the symmetry of the magnetic orbitals. The concept of overlap density is introduced. It permits an estimation of the magnitude of the ferromagnetic stabilization in the case of orthogonality of the magnetic orbitals. The Cu(II)-Fe(III) interaction, in relation to the situation encountered in cytochrome oxidase, the Cu(II)-Ni(II) interaction and a few additional selected examples are discussed. A section deals with the case where one of the interacting ions has an orbital degeneracy. Afterwards, the heterotrinuclear complexes are studied. The important concept of regular and irregular spin state structure is developped and the Mn(II)Cu(II)Mn(II) triad is presented as a spectacular example of irregular spin state structure. A section is devoted to the ordered bimetallic chains. The theory is presented, both at a qualitative and quantitative levels and the already reported compounds of this kind are discussed. One of them may be considered as one of the first molecular ferromagnets. The last but one section concerns the systems with even more subtle spin orders. In conclusion, the vast perspectives of this area are outlined.

Magnetism of the heteropolymetallic systems

Study of the relation between the structural data and magnetic interaction in oxo-bridged binuclear copper(II) compounds

S. J. Gruber

Papers

Metal complexes as ligands—IV [1,2,3]: Bi- and Tri- nuclear complexes derived from metal complexes of tetradentate salicylaldimines

Metal complexes as chelates. II. Binuclear complexes containing similar and dissimilar metal atoms

Metal complexes as ligands bi- and tri-nuclear complexes containing similar and dissimilar metal atoms

Metal complexes as ligands III1 structures of BI- and tri-nuclear compounds derived from salicylaldimine complexes