Electronic structure of NaNbO3-Mn single crystals

The XPS spectra of the NaNbO3 single crystals doped with manganese (x = 0. 1, 0.5, 1.0, 3.0, 5.0 and 10.0%) were measured using the PHI 5700/660 physi cal electronics photoelectron spectrometer at room temperature within the a ntiferroelectric phase. From the spectra the atomic concentration was calcu lated and compared to the nominal composition. The approximate solubility l imit of the Mn ions, built into the sodium niobate crystal lattice, was det ermined as 1.0% Mn. The dependence of the core level peak position and vale nce band on manganese dopant was determined. The influence of sputtering wi th the Ar+ ions on the Nb core line and valence band shape was observed. Th is effect was ascribed to the change in niobium valence due to the oxygen d efects produced during the sputtering process. (C) 2001 Elsevier Science B. V. All rights reserved.