The Coulomb explosion of swift C2+ molecules under channeling conditions

We have bombarded crystalline Si with high-energy (1.847 MeV/atom) atomic C+ and molecular C2+ ions in 〈1 1 1〉, 〈1 0 0〉 and 〈2 1 1〉 axial channeling and in random directions to observe the effect of Coulomb explosion (CE) for the molecular ions. The energy spectra of backscattered ions measured with equivalent fluences of atomic and molecular ions are compared. In channeling spectra measured with C+ and C2+ beams the significant de-channeling due to damage build-up caused by the irradiation was found to be equal for atoms and molecules and linearly increasing with fluence in the studied range. In addition to the damage effect the CE effect was clearly observed for the three channels studied.