Recent advances in bioinorganic spectroscopy

Spectroscopic methods covering many energy regions together provide complementary insight into metalloenzyme active sites. These methods probe geometric and electronic structure and define these contributions to reactivity. Two recent advances - determination of the polarizations of electronic transitions in solution using magnetic circular dichroism, electron paramagnetic resonance and quantum chemistry. and experimental estimation of covalency using metal L-edges and ligand K-edges - are particularly important.