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.
Categories: cond-mat.str-el cond-mat.mtrl-sci