The United Atom Treatment of H2+

Using first-order perturbation theory on the united atom, closed expressions are obtained for the energies, and the charges which minimize those energies, of the following states: 1sσ, 2pσ, 2pπ, 3pπ, and 3dδ. Numerical calculations based on these expressions show, for the higher states, quite good agreement with the more exact calculations of Teller and Chakravarty.