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Electronic structure of Pr$_{0.67}$Ca$_{0.33}$MnO$_3$ near the Fermi level studied by ultraviolet photoelectron and x-ray absorption spectroscopy

M. K. Dalai·P. Pal·B. R. Sekhar·N. L. Saini·R. K. Singhal·K. B. Garg·B. Doyle·S. Nannarone·C. Martin·F. Studer
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Abstract

We have investigated the temperature-dependent changes in the near-$E$$_F$ occupied and unoccupied states of Pr$_{0.67}$Ca$_{0.33}$MnO$_3$ which shows the presence of ferromagnetic and antiferromagnetic phases. The temperature-dependent changes in the charge and orbital degrees of freedom and associated changes in the Mn 3$d$ - O 2$p$ hybridization result in varied O 2$p$ contributions to the valence band. A quantitative estimate of the charge transfer energy ($E$$_{CT}$) shows a larger value compared to the earlier reported estimates. The charge localization causing the large $E$$_{CT}$ is discussed in terms of different models including the electronic phase separation.

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M. K. Dalai, P. Pal, B. R. Sekhar, N. L. Saini, R. K. Singhal, K. B. Garg, B. Doyle, S. Nannarone, C. Martin, F. Studer. 2006-10-16. Electronic structure of Pr$_{0.67}$Ca$_{0.33}$MnO$_3$ near the Fermi level studied by ultraviolet photoelectron and x-ray absorption spectroscopy. https://doi.org/10.1103/physrevb.74.165119

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