Photo-Ionization And Fragmentation Of Sc3n@C-80 Following Excitation Above The Sc K-Edge

We have investigated the ionization and fragmentation of a metallo-endohedral fullerene, Sc3N@C-80, using ultrashort (10 fs) x-ray pulses. Following selective ionization of a Sc (1s) electron (h nu = 4.55 keV), an Auger cascade leads predominantly to either a vibrationally cold multiply charged parent molecule or multifragmentation of the carbon cage following a phase transition. In contrast to previous studies, no intermediate regime of C-2 evaporation from the carbon cage is observed. A time-delayed, hard x-ray pulse (h nu = 5.0 keV) was used to attempt to probe the electron transfer dynamics between the encapsulated Sc species and the carbon cage. A small but significant change in the intensity of Sc-containing fragment ions and coincidence counts for a delay of 100 fs compared to 0 fs, as well as an increase in the yield of small carbon fragment ions, may be indicative of incomplete charge transfer from the carbon cage on the sub-100 fs time scale.