Ab initio calculation of the electrical properties of the X2Πg ground state of O2+

The potential energy, quadrupole moments and dipole polarisabilities have been calculated at the full valence space CASSCF level using a [8s6p3d] basis for the ground X2Πg state of O2+ as a function of internuclear distance. Vibrationally averaged values are also calculated for the quadrupole moments and spherical and anisotropic polarisabilities for ν = 0−3. The results are compared with calculations and experimental values for N2+, NO+ and CO+.