Vibrationally selective autoionization of physisorbed molecular nitrogen

Autoionization from vibrationally resolved core excited states is demonstrated, using nitrogen physisorbed on graphite. The results are compared to photoemission and x-ray absorption, and reveal an adsorption induced elongation of the internuclear separation in the 3${\mathrm{\ensuremath{\sigma}}}_{\mathit{g}}^{\mathrm{\ensuremath{-}}1}$ final state. It is demonstrated that it is only in the case of vibrationally selective excitation that the autoionization final states coincide with the photoemission final states.