Valence States of Rare-Earth Ions in RERuSn₃ (RE=La, Ce, Pr, Nd, Sm) and Related Compounds Studied by Core-Level Photoemission Spectroscopy

抄録

We have measured the 3d and 4d core-level X-ray photoelectron spectra of rare earths in RERuSn₃ (RE=La, Ce, Pr, Nd and Sm) and related rare-earth compounds. The Ce 3d spectra of CeRuSn_x (x=2.85, 3.0 and 3.15) show the common features observed in other cerium compounds. In the spectra, f⁰ structures cannot be apparently distinguished from other prominent structures f¹ and f² peaks, and broad structures are observed at the high binding energy side of the f¹ peak. For SmRuSn₃, both Sm 3d and 4d spectra show strong Sm²⁺ components and the Sm valency is estimated to be 2.95±0.02.