Experimental electronic structures of copper complexes with a biphenyldiimino dithioether - a model for blue copper proteins.

The experimental electron density distributions in two coordination compounds - one with a central Cu(I) atom and the other with Cu(II), coordinated by the same biphenyldiimino dithioether (bite) type of ligand - have been obtained from high-resolution X-ray reflection data to model the possible electron predisposition for the redox reaction in blue copper proteins. The bite ligand has been adapted to the conformation required by the central atom.