Neutral and Multicharged Ions of Small Aluminum Oxides: Structures, Spectroscopy, and Energetics

We use accurate ab initio methodologies at the Coupled Cluster level to compute the stable forms of Al_xO_y^q+ (x = 1, 2; y = 1, 2; q = 0–3) species for which we derive an accurate set of geometrical and vibrational spectroscopic data. We also determine their adiabatic single, double, and triple ionization energies. These spectroscopic and thermodynamical data may help for identifying these species in laboratory, in astrophysical media, and in plasma and confirm previous observations of multi-charged Al_xO_y clusters by Atom Probe Tomography (ATP) coupled to mass spectrometry. They should help for identifying and understanding the complex chemical processes occurring during the Al₂O₃ growth in laboratory and in astrophysical media and those taking place at the degradation of Al-containing materials by high temperature corrosion/oxidation.