Multiple dumbbell structures of vanadium–C60 clusters

Vanadium (V)–C60 mixed clusters were produced by two laser vaporization methods. In the mass spectra of cationic Vn(C60)m+, the abundant clusters were produced at the composition of (n,m)=(1,1), (1,2), (2,3), (3–4,4), and (5,5). This pattern is explicable in terms of a multiple dumbbell structure; V atom and C60 are alternatively piled up. The ionization energy and the reactivity of the dumbbell clusters toward O2 and CO show V1(C60)2 takes a structure of V1(η6−C60)2.