Molecular Description of Two-Electron Atoms

Abstract

We show that the use of the interelectronic vector as adiabatic axis allows two-electron states of atoms to be described in terms of molecular orbitals. The associated potential curves can be obtained by scaling calculations on the ${\mathrm{H}}_{2}^{+}$ molecular ion and show for doubly excited states a strong similarity to adiabatic curves obtained from an analysis in hyperspherical coordinates. We associate a definite molecular symmetry with each two-electron state.