X-ray emission and photoelectron spectra ofPr0.5Sr0.5MnO3

Abstract

The results of measurements of x-ray photoelectron ͑XPS͒, x-ray emission ͑XES͒, and x-ray absorption spectra and local spin-density approximation band structure ͑LSDA͒ calculations of Pr 0.5 Sr 0.5 MnO 3 are presented. The excitation energy dependence of Mn L 2,3 and O K␣ x-ray emission spectra of Pr 0.5 Sr 0.5 MnO 3 is measured using tunable synchrotron radiation. The XES measurements yielded no photon energy dependence for the O K␣ spectra, but the Mn L 2,3 spectra yielded inelastic scattering losses of 2 and 6 eV, corresponding to features in the structure of the occupied part of the valence band. Comparing XPS and XES measurements with LSDA band-structure calculations, one concludes that the electronic structure of the compound consists mainly of Mn 3d and O 2p states. States of 3d character localized at the Mn site predominate near the top of the valence band ͑VB͒. Some differences in the Mn 3d distribution in this part of the XPS valence band and Mn L 3 XES with d symmetry due to spin-selection rules that govern the Mn L 3 XES. In addition, the Mn 3d states distribution is hybridized with the O 2 p part of the VB. Mn L 3 XES spectra were determined relative to the Fermi energy by assuming normal x-ray emission begins from the lowest level of the p 5 d nϩ1 L intermediate state ͑which is the Mn 2p ionizatation threshold͒. From the local spin-density approximation, the orbital character of the Mn 3d electrons can be assigned e g symmetry at the top of the valence band T 2g in the central part of the VB, and equal contributions of e g and t 2g states at the bottom of the valence band.

Core photoemission spectra of oxygen atoms in perovskite manganites La 1−x A x MnO 3 (A=Sr, Pb)

“…The spectra exhibit two dominant peaks (one at around 529 to 530 eV, and tile other at about 531 eV), similar to those observed with high-Tc superconductors [8,9,10] and for Sr2Ru04 [11] and Pro.sSro.sMn03 [12]. The binary manganese oxides show just one dominant peak O(ls) [13], characteristic of the lattice 0 -2 and comparable to the lower binding energy peak of tile perovskite materials.…”

Chromium deposition and poisoning of La0.8Sr0.2MnO3 oxygen electrodes of solid oxide electrolysis cells

“…This indicates the Mn valence state is between 3+ and 4+. 37,40 On the other hand, under the rib of the interconnect there is a shi of Mn2p 3/2 to a lower binding energy of 639.5 eV (spectrum iii, Fig. 9d), which suggests the presence of MnO.…”

Fabrication of hierarchical porous MnCo2O4 and CoMn2O4 microspheres composed of polyhedral nanoparticles as promising anodes for long-life LIBs

“…The cyclic voltammetry (CV) test was carried out in the potential window of 0.01 V to 3.0 V by an electrochemical workstation (CHI 760e). 28 Magnitude of peak splitting is diagnostic of oxidation state. In this study, uniform carbonate precursors were firstly fabricated by a solvothermal method.…”