Two-color pump-probe study and internal-energy dependence of Rydberg-state excitation in C60 -: art. no. 051201

Excitation of Rydberg states in isolated C-60 is studied by time-resolved photoelectron spectroscopy in a femtosecond two-color pump-probe experiment. The relaxation time for electron-electron interaction is determined to be approximately 100 fs with the t(1g)(LUMO+1) orbital being considered to define the doorway state in a nonadiabatic multielectron excitation process. The internal energy stored in vibrational modes of the C-60 at 770 K is found to support the excitation process very efficiently while in "cold" C-60 (80 K), no significant Rydberg population is detected.