Bond formation in momentum space

The effects of bond formation on the electron density are examined both in momentum space and in the more familiar position-space representation. We consider three very different diatomic molecules over a wide range of nuclear separations using flexible wavefunctions which allow for proper dissociation. For this purpose we employ the spin-coupled theory, which is a modern valence-bond approach based on a simple picture of singly occupied orbitals which are generally highly localized. This makes possible a study of the effects of bond formation on individual momentum-space orbitals.