Sc2S@C2(7892)-C70: a metallic sulfide cluster inside a non-IPR C70 cage

A new cage isomer of C-70, Sc2S@C-2(7892)-C-70, has been isolated and characterized by mass spectrometry, UV-Vis-NIR absorption spectroscopy, cyclic voltammetry and DFT calculations. The combined experimental and computational studies lead to the unambiguous assignment of the cage symmetry to C-2(7892)-C-70. The comparison between Sc2S@C-2(7892)-C-70 and related endohedral structures has been discussed. A close structural resemblance between Sc2S@C-2(7892)-C-70 and Sc2S@C-s(10 528)-C-72 suggests that the conversion of these two molecules may be the result of a simple insertion of C-2 and the structural difference between Sc2S@C-2(7892)-C-70 and Sc3N@C-2v(7854)-C-70 shows that the nature and geometry of the encaged cluster plays an important role on the selection of the non-IPR cage.