Spectroscopy of AlAr and AlKr from 31 000 cm-1 to the ionization limit

Spectra of jet-cooled AlAr and AlKr have been collected over the range from 31 000 cm -? to the ionization limit, using the technique of resonant two-photon ionization spectroscopy with mass spectrometric detection. Adiabatic ionization potentials have been accurately measured for both molecules, and have been estimated for AlAr? and AlAr?. The spin-orbit splittings in the X ?II ground state have been determined for both AlAr and AlKr, and ground-state bond strengths have been accurately measured as Do [AlAr, Xi ?II1/2 (3p)] = 122.4 ? 4 cm-? and D?[27A1 84Kr, X, ?II1/2 (3p)] = 194.7 ? 0.8 cm-? . These values have also been combined with the measured ionization potentials to derive D?(Al+-Ar) = 982.3 ? 5 cm-? and D?(Al+-Kr) = 1528.5 ? 2cm- ?.