Ab initio treatment of gas phase GeO2+ doubly charged ion

- Theoretical investigation of the novel gas-phase molecular species GeO2+.
- Spectroscopic parameters of this dication in its electronic ground and exited states.
- Theoretical double ionization spectrum of GeO.

Using multi reference configuration interaction methodology in connection with a large basis set, we show that GeO2+ is a metastable species either in the ground or in the electronically excited states. This confirms the observation of this dication in gas phase by mass spectrometry. In addition, we derived a set of accurate spectroscopic terms for GeO2+ bound states. At the MRCI/aug-cc-pV5Z level of theory, the adiabatic double ionization energy of GeO is computed to be ∼28.93 eV.