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

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.

19 pages, 7 figures, To be published in Phy. Rev. B