Anab initio study of the molecules P2O and P2O+

Summary This paper presents a detailedab initio study of the molecules P₂O and P₂O⁺ at the Hartree-Fock, and Multi-Reference Single and Double Excitation Configuration Interaction levels. An analysis of the geometries and relative stabilities of both molecules is presented, together with a discussion of the dissociation channels and of the electronic spectrum of linear P₂O. The results for the ionic species P₂O⁺ suggest a cyclic geometry for this molecule, as indicated by the calculated vibrational frequencies. The calculations also indicate a surface crossing at a relatively low energy which might lead to P₂O dissociation and may hence be one of the factors contributing to the failure to detect it at room temperatures.