The Electronic Structure of Lanthanide Impurities in TiO2, ZnO, SnO2, and Related Compounds

The vacuum referred binding energy of electrons in the 4fn levels for all divalent and trivalent lanthanide impurity states in TiO2, ZnO, SnO2, and related compounds MTiO3 and MSnO3 (M = Ca2 +, Sr2 +, Ba2 +) and Ca2SnO4 are presented. They are obtained by collecting data from the literature on the spectroscopy of lanthanide ions, and by combining that data with the chemical shift model. The model provides the energy at the top of the valence band and at the bottom of the conduction band, and it will be shown that those energies are in excellent agreement with what is known from techniques like photo-electron spectroscopy and electrochemical studies. Electronic level diagrams are presented that explain and predict aspects like absence or presence of lanthanide 4f-4f or 5d-4f emissions and the preferred lanthanide valence.RST/Radiation, Science and TechnologyApplied Science