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arXiv · 0907.5455

Evidence for Oxygen Holes due to d-p Rehybridization in Thermoelectric Sr_{1-x}Rh_{2}O_{4}

Y. Ishida·T. Baba·R. Eguchi·M. Matsunami·M. Taguchi·A. Chainani·Y. Senba·H. Ohashi·Y. Okamoto·H. Takagi·S. Shin
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Abstract

Soft-x-ray photoemission and absorption spectroscopies are employed to investigate the electronic structures of Sr_{1-x}Rh_{2}O_{4}. Similarly to the layered cobaltates such as Na_{1-x}CoO_{2}, a valence-band satellite feature (VBS) occurs at higher binding energy to the O 2p band. We find that the VBS resonates at the O 1s edge. Additionally, core absorption shows clear x dependence in the O 1s edge rather than in the Rh 3p edge. These results indicate that the holes in the initial state mainly have O 2p character presumably due to d-p rehybridizations affected by Sr^{2+} vacancy potentials. The resultant inhomogenous charge texture may have impact on the TE transport properties at low x.

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Y. Ishida, T. Baba, R. Eguchi, M. Matsunami, M. Taguchi, A. Chainani, Y. Senba, H. Ohashi, Y. Okamoto, H. Takagi, S. Shin. 2009-07-31. Evidence for Oxygen Holes due to d-p Rehybridization in Thermoelectric Sr_{1-x}Rh_{2}O_{4}. https://doi.org/10.1103/physrevb.80.081103

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