Collision of low energy Na+ ion with C60

The collision-induced reaction of Na+ ion with neutral C60 vapour was investigated at the energy range of 10 to 150 eV. The deposited films were studied via laser desorption time-of-flight mass spectroscopy (TOFMS). The fragment products of C60 with even number of carbon atoms, such as Cn+ (n=58, 56, 54), and adduct products, such as Cn+ (n=62, 64, 66, 68) were observed in the positively charged TOF mass spectra. The endohedral fullerene ion of Na+C60+ was detected when collision energies are above 20 eV. Besides, no negative endohedral fullerene was detected, the products appearing in positively charged mass spectra were also observed in the negatively charged mass spectra. In addition, a series of products with odd number of carbon atoms, such as Cn- (n=53, 55, 57, 59, 61, 63, 65, 67), also appeared, but the intensities of their signals were not as high as that of even numbered. Finally, it is interesting to find that the deposited films are insoluable in toluene, benzene or water. Their Fourier transform infrared (FTIR) spectra seem like those photopolymerized ones. Some of the reaction schemes are proposed to explain the experimental reuslts