Laser mass spectrometry study of the properties of fullerene structures

Fullerene films grown by various methods are studied using mass spectrometry. The mass spectra of the films formed onto an aluminum foil using thermal deposition (TD) or supersonic molecular beam (SMB) exhibit a small change in the mass peak distribution in the C120 dimer range as compared to the initial fullerene powder during desorption by laser radiation irrespective of the radiation wavelength (λ = 259, 518 nm). Under the action of laser radiation with wavelength λ = 259 nm, fullerene films grown on a silicon substrate with an SMB also exhibit a small change in the mass peak distribution in the C120 dimer range. At λ = 518 nm, the mass peak distribution in the dimer range shifts significantly toward small masses, so that the intensity maximum corresponds to M ≅ C102. This fact is assumed to be related to the polymerization of an SMB fullerene film caused by heating due to the absorption of laser radiation with a wavelength λ = 518 nm.