Metastable He2- ions formed by two-electron attachment to the excited He2+ g+2 (1g22g1) core

Four metastable states (1 u4, 2 u4, u4, and 4Iu), resulting from two-electron attachments to the excited He2+ core (2g+), are characterized using the numerical Hartree-Fock method. It is determined that such metastable states are formed when both valence electrons are placed into equally diffused orbitals, which have bonding charter, and whose angular momentum quantum numbers do not differ by more than 1.