Probing molecular symmetry effects in the ionization of N-2 and O-2 by intense laser fields

摘要

High-resolution electron spectroscopy is used to explore the role played by molecular symmetry in determining the morphology of the energy spectra of electrons ejected when N-2 and O-2 are irradiated by intense laser fields. In O-2, the low-energy part of the electron spectrum is curtailed due to the destructive interference brought about by the antibonding nature of the O-2 valence orbital. The high-energy tail of the spectrum is also suppressed by virtue of electron rescattering being of little consequence in O-2. In contrast, in N-2, which has a bonding valence orbital, the electron dynamics follow the pattern that has been established for atomic ionization in strong optical fields. (C) 2007 American Institute of Physics.