Metals in biology: Electronic structure,properties and charge transfer for copper complexes of glyoxal and dithiene

Summary In an attempt to study the role of metals in biologyab initio SCF calculations have been performed on a model complex simulating the binding between metals and biological materials. There is a certain distinction between the copper complexes compared to the other transition metals and in many cases the copper complexes are more similar to the Li and Be complexes than to other transition metal complexes. One special feature of the copper complexes is their strong ability for an easy transfer between the Cu(I) and Cu(II) states, allowing for a very flexible charge transfer with small energies required for the redox processes. These processes have been described in terms of orbital energies and Mulliken populations.Dedicated to Professor Inga Fischer-Hjalmars on the occasion of her 75th birthday