Hot electron production and diffuse excited states in C70, C82, and Sc3N@C80 characterized by angular-resolved photoelectron spectroscopy

Angular-resolved photoelectron spectroscopy using wavelength-tuneable femtosecond laser pulses is presented for a series of fullerenes, namely, C-70, C-82, and Sc3N@C-80. The photoelectron kinetic energy distributions for the three molecules show typical thermal electron spectra with a superimposed peak structure that is the result of one-photon ionization of diffuse low-angular momenta states with electron density close to the carbon cage and that are related to so-called super atom molecular orbitals. Photoelectron angular distributions confirm this assignment. The observed structure is less prominent compared to the thermal electron background than what was observed in C-60. It can be concluded that hot electron emission is the main ionization channel for the larger and more complex molecules for these excitation conditions. (C) 2013 AIP Publishing LLC.