Electronic band structure and photoemission states of La0.67Pb0.33Mn1−xFexO3

Abstract

The calculation was carried out in manganese perovskite La0.67Pb0.33Mn1−xFexO3 for x=0, 0.083 (1/12) and 0.33 based on the first-principles Density Functional Theory with general gradient approximation GGA+U using WIEN2k package. The P3¯c1 crystal structure was taken from the X-ray diffraction data for the perovskite. The original unit cell was multiplied twice for x=0.083 in all direction and twice in c for x=0 and x=0.33 in order to place proper amount of Fe. Final crystal structure with 120 atoms was used for calculation x=0.083. For Mn and Fe d electrons the exact exchange energy was utilized. As a results half-metallic density of state was obtained with top of valance band for spin down 1.5eV below EF and spin up filled up to Fermi level by d electrons of Mn, Fe and oxygen p electrons. Comparison of total DOS with ultraviolet photoemission spectra shows similar features up to −10eV and especially the decrease in DOS from −2eV to EF.