Assigning Reactive Excited States in Inorganic Photochemistry

The matter of assigning reactive excited states in inorganic photochemistry turns out to have complexities as more detailed and more varied information is obtained. Three cases are considered. For Cr(III) ammines there is still much controversy in the assignment of chemical reactivity to doublet and quartet states. In the case of Rh(NH3)5X2+ complexes, it may be necessary to invoke three different reactive or emitting ligand-field excited states, while for W(CO)5L species, at least two, including a charge transfer state, are needed.