Photoprocesses of the endohedral fullerene ions ${\mathrm{Sc}}_3\mathrm{N}@{\mathrm{C}}_{80}^{+}$ and ${\mathrm{Sc}}_3\mathrm{N}@{\mathrm{C}}_{80}{}^{-}$ in the gas phase have been investigated in the photon energy ranges 30–50 eV and 280–420 eV. Single and double ionization as well as single ionization accompanied by the release of a ${\mathrm{C}}_2$ dimer were observed as a function of the photon energy for the positive parent ion and double detachment was measured for the negative parent ion. The emphasis of the experiments was on the specific effects of the encapsulated trimetallic nitride cluster ${\mathrm{Sc}}_3\mathrm{N}$ on the observed reactions. Clear evidence of photoexcitation near the Sc $L$ edge is obtained with the dominating contributions visible in the one- and two-electron-removal channels. $K$-vacancy production in the encapsulated central nitrogen atom is seen in the single ionization of ${\mathrm{Sc}}_3\mathrm{N}@{\mathrm{C}}_{80}^{+}$ but is much less pronounced in the photoionization-with-fragmentation channel. Comparison of the cross sections near the carbon $K$ edge with the corresponding channels measured previously in the photoionization of ${\mathrm{Lu}}_3\mathrm{N}@{\mathrm{C}}_{80}^{+}$ reveal strong similarities. Previously predicted sharp resonance features in the ionization of ${\mathrm{Sc}}_3\mathrm{N}@{\mathrm{C}}_{80}^{+}$ ions below the Sc $M$ edge are not confirmed. The experiments are accompanied by quantum-chemistry calculations in the Hartree-Fock approximation and by model calculations employing density functional theory (DFT).

• Received 25 February 2019

DOI:https://doi.org/10.1103/PhysRevA.99.063401