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Electronic structure and electron energy-loss spectra of Sr0.35CoO2

R. J. Xiao·H. X. Yang·L. F. Xu·H. R. Zhang·Y. G. Shi·J. Q. Li
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Abstract

The electronic structure of Sr0.35CoO2, structurally analogous to the layered NaxCoO2, has been evaluated using the local spin density approximation (LSDA). We find that evident c-dispersions appear in both the e'g and a1g Co-derived bands, demonstrating the existence of a notable interplanar interaction in Sr0.35CoO2. The LSDA+U calculation reveals that the electronic structure, in particular the band splitting between the spin-up and spin-down electrons, changes evidently along with the increase of the effective on-site Coulomb interaction U. Analysis of theoretical and experimental electron energy-loss spectra (EELS) for the oxygen K-edge and the Co L23-edge suggests that the on-site interaction (U) in Sr0.35CoO2 is less than 3eV which is noticeably weaker than the estimated value (from 5eV to 8eV) in the NaxCoO2 materials.

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R. J. Xiao, H. X. Yang, L. F. Xu, H. R. Zhang, Y. G. Shi, J. Q. Li. 2006-12-07. Electronic structure and electron energy-loss spectra of Sr0.35CoO2. https://arxiv.org/abs/cond-mat/0612182

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