Angle-resolved study of resonant Auger decay and fluorescence emission processes after core excitations of the terminal and central nitrogen atoms inN2O

Abstract

Angular distributions of the ${\mathrm{N}}_{2}$${\mathrm{O}}^{+}(X)$ and ${\mathrm{N}}_{2}$${\mathrm{O}}^{+}(A)$ photoelectrons were measured as functions of the exciting-photon energy with small bandwidth in the vicinity of the resonant ${\mathrm{N}}_{t}(1s\ensuremath{\rightarrow}{\ensuremath{\pi}}^{*})$, ${\mathrm{N}}_{t}(1s\ensuremath{\rightarrow}{\ensuremath{\sigma}}^{*})$, and ${\mathrm{N}}_{c}(1s\ensuremath{\rightarrow}{\ensuremath{\pi}}^{*})$ core excitations of ${\mathrm{N}}_{2}\mathrm{O}$. For selected exciting-photon energies in this range, angular distribution parameters of the ${\mathrm{N}}_{2}$${\mathrm{O}}^{+}(A\ensuremath{\rightarrow}X)$ fluorescence were also determined. These data are interpreted by ab initio calculations. Long-range exciting-photon energy dependencies of the photoelectron angular distribution parameters ${\ensuremath{\beta}}_{X}^{e}(\ensuremath{\omega})$ and ${\ensuremath{\beta}}_{A}^{e}(\ensuremath{\omega})$, recorded vibrationally unresolved, are attributed to an electronic state interference between the direct and the different resonant amplitudes for the population of the final ionic states. In addition to that, strong influence of lifetime vibrational interference is identified in the observed dispersion of the vibrationally resolved fluorescence angular distribution parameter $\ensuremath{\beta}{2}_{A}^{X}(\ensuremath{\omega})$ across the electronic resonances.