Resonant photoemission of transition metal perovskites
We discuss the use of resonant photoemission in the study of rare earth/transition metal perovskites and perovskite-related structures. We illustrate its application to the assignment of the RE and TM valence band density of states in Nd2Ni1-xCuxO4 and REBaCo2O5+δ. In both cases, the relative positions of the 4f and 3d contributions within the valence band density of states (DOS) relative to the Fermi energy provide a rationalisation of the redox behaviour of the system. We also apply the technique to the determination of the Co spin state in Co(III) perovskites such as LaCoO3 and GdBaCo2O5+δ, where the observation of a delayed Co 3p → 3d resonance is a powerful diagnostic of the Co(III) low spin state. This reveals that while the Co(III) ions in LaCoO3 increasingly populate the low spin state as the sample temperature is lowered, a significant proportion of the Co(III) species in GdBaCo2O5+δ are not in the low spin state at temperatures as low as 50 K. © 2005 Elsevier B.V. All rights reserved.
Publication Source (Journal or Book title)
Journal of Electron Spectroscopy and Related Phenomena
Flavell, W., Thomas, A., Tsoutsou, D., Mallick, A., Hollingworth, J., Patel, S., Seddon, E., Stockbauer, R., Kurtz, R., Sprunger, P., Barilo, S., Shiryaev, S., & Bychkov, G. (2005). Resonant photoemission of transition metal perovskites. Journal of Electron Spectroscopy and Related Phenomena, 144-147, 777-782. https://doi.org/10.1016/j.elspec.2005.01.149