The vacuum referred electron binding energies in the 1S0 and 3P1 states of Pb2+ and Tl+ in inorganic compounds

An overview of the spectroscopic data on Tl+ and Pb2+ in 37 and 126 different inorganic compounds, respectively, is presented. Using the metal-to-metal charge transfer and A-band transition energies, the electron binding energies in the S-1(0) ground state and P-3(1), excited state of Tl+ and Pb2+ were determined relative to the vacuum level. By constructing vacuum referred binding energy (VRBE) diagrams that display the energy levels of the Tl+ and Pb2+ activator ion together with that of the host compound, insight in the luminescent properties of these activated compounds are gained. The obtained VRBEs of the electron in the S-1(0), and P-3(1), states of Tl+ and Pb2+ are compared to those of Bi3+.