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Zusammenfassung

We present a combined experimental and theoretical Pb-L3 X-ray absorption near-edge spectroscopy (XANES) to investigate the chemical state of Pb in transition metal perovskites PbTMO3 (TM = Ti, Ni). A pre-edge feature originated from the excitation of a 2p core electron to the 6s orbital is only observed in PbNiO3, from which the valence of Pb is determined to be Pb4+ with two 6s holes. However, no such 2p–6s related excitation was observed in PbTiO3, indicating the formation of Pb2+ with fully occupied 6s2 state in this materials. Our results demonstrate that this pre-edge peak from dipole allowed 2p–6s transition is a sensitive finger-print of the Pb valence state in solid state materials.