Coupled cluster calculations with numerical orbitals for excited states of polar anions

A recently proposed technique, which combines numerical orbitals for diatomic systems with coupled cluster methods, has been applied to study excited states of negative ions of polar molecules. Computational strategy is presented and calculations of ground and excited state electron affinities are reported for the LiH and BeO molecules. LiH and BeO are found to have excited state electron affinities of 0.0028 and 0.0234 eV. Both excited state affinities should be amendable to experimental determination.