Surface ionization mass spectrometric studies of the Li/C-60 system

We have studied the Li/C-60 system by the surface ionization mass spectrome try. We have investigated a possibility of the Li@C-60 formation via the co llisions between Li+ and C-60(-) ions in a plasma state, which was Predicte d by an ab initio molecular dynamics simulation. The LiC60 complex was unam biguously observed. Our results do not allow direct determination of the Li C60 structure but indicate that Li is inside the C-60 cage. We have determi ned the ionization potential of Li@C-60 complex (TP = 5.9 +/- 0.1 eV), whic h agrees well with the calculated value of the IP of Li@C-60.