X-ray optical activity in 4d and 5d metal complexes

The aim of this proposal is to elucidate the role of p-d orbital hybridization on the X-ray Natural Circular Dichroism (XNCD) response. In this project, we will acquire original experimental data to validate theory and use in the development of tools to simulate XNCD spectra to open this technique to the chemistry community. The proposed systems consist of single crystals containing the group 7 metals − cobalt, rhodium and iridium − measured at the metal K- and L- edges. The chosen chiral molecules, [M(chxn)3](NO3)3٠3H2O, provide isostructural models where the only change is the valence d shell, going from 3d in cobalt to 5d in iridium. We hypothesize that the more diffuse d orbitals in the heavier metals will result in a larger p-d hybridization and thus a larger relative XNCD response.