Electronic structure of Pr1-xCaxMnO3Pr1-xCaxMnO3 from photoemission and inverse photoemission spectroscopies

We have studied the occupied and unoccupied electron states of the Pr1-xCaxMnO3Pr1-xCaxMnO3 (x=0.2x=0.2, 0.33 and 0.4) near the Fermi level across their ferromagnetic–antiferromagnetic phase boundary using ultraviolet photoemission spectroscopy and inverse photoemission spectroscopy. The photoemission data show that the pseudogap formation in these compounds occur over an energy scale of 0.48±0.02eV. From a combined analysis of the photoemission and inverse photoemission results, we have estimated the charge transfer energy in these compounds to be ∼2.8±0.2eV. The results have been explained on the basis of the theoretical models that describe the electronic phase separation.