Correlated prolate–spheroidal wave functions for the excited states 1,3Σg+(1sσg, 2sσg) of H2 and He22+

Abstract
The total energy of the excited states 1,3Σg+(1sσg, 2sσg) of H2 and He22+ has been calculated for several values of the internuclear distance from a one‐parameter correlated prolate–spheroidal wave function. Such diabatic results are seen to be in fairly good agreement with the best adiabatic ones outside the avoided‐crossing regions.