CAGE DESTRUCTION IN METAL-FULLERENE CLUSTERS

Mass spectrometric studies on free clusters composed of single fullere ne molecules and transition metal atoms (C(60)M(x) and C(70)M(x); x=0, ...,150; M is an element of{Ti, V, Nb, Ta}) reveal that they undergo a laser induced transformation from metal-fullerene clusters to metal c arbide and metallo-carbohedrene clusters. Two types of fragmentation b ehavior are observed. Fullerenes doped with titanium or vanadium seem to be stable at low laser intensities, whereas tantalum and niobium se verely destabilize the fullerene cage. Photofragmentation spectra of p reselected C60Tax indicate that the C-60 cage is destroyed for x great er than or equal to 3.