Electronic Structure of Metallofullerene, Tm@C82 (II)

Ultraviolet photoelectron spectra of one of three Tm@C82 isomers, Tm@C82 (II), were measured with synchrotron radiation light source. The spectra resemble those of Ca@C82 (III), which indicates that these two metallofullerenes have analogous valence electronic structures as well as the cage structures. The spectra of Tm@C82 (II) and Ca@C82 (III) are well reproduced by a simulated spectrum obtained with ab initio calculation based on the C2 (no.5) cage geometry. This finding supports symmetry group determination carried out with NMR measured on Tm@C82 (II). Because of spectral resemblance, the electronic structure of metallofullerenes seems to be determined solely by the fullerene cage and entrapped atom species.