Core-level photoemission of Sm fullerides

Phases and core-levels of Sm-intercalated C-60 thin films are researched with X-ray photoemission spectroscopy. The solid solution phase dominates until the stoichiometry of Sm-0.5 C-60. Below the intercalation level Of SM2.75 C-60 I the sample is phaseseparated into the solid solution phase and Sm-2.75 C-60 I while the sample is not the mixture of Sm-2.75 C-60 and Sm-6 C-60 with the Sm concentration higher than SM2.75 C-60. Experimental data of Sm 4f and 4d clearly reveal the valence state of Sm is divalent for Sm fullerides. Two subpeaks of divalent Sm 3d(5/2) level are found.