An « open shell » type wave function for the hydrogen molecule ground state

The energy of the H2 molecule is calculated by using an « open shell » function analogous to the one used by Hylleraas for the He atom. In this way radial correlation is introduced without explicit inclusion of terms containing the interelectron distancer12. The calculated dissociation energy (4.17 eV) is one of the best values obtained in this approximation. A comparison with a similar wave function suggested by Muller and Eyring is made.