Lanthanide level location in transition metal complex compounds

We will provide a method to place the levels of all trivalent lanthanides with respect to the top of the valence band and bottom of the conduction band in oxides containing transition metal complexes. The method will be applied to CaTiO(3), YVO(4), LaVO(4), CaNb(2)O(6), YNbO(4), CaWO(4), YTaO(4), and LaTaO(4), but in principle can be applied to any oxide containing transition metal complexes with lanthanide dopants on either rare earth or alkaline earth sites. Crucial to place the energy levels is the energy for intervalence charge transfer between a lanthanide (Fr(3+) and Tb(3+)) and a transition metal ion (Ti(4+), V(5+), Nb(5+), Mo(6+), Ta(5+), W(6+)) that can be observed in luminescence excitation spectra. The quenching of Pr(3+) emission from the (3)P(0) state and of Tb(3+) emission from the (5)D(3) and (5)D(4) states provides complementary information.