Topology of electron correlation in the b 3Σ+u state of the H2 molecule

Except for the united atom limit, the correlation cage of the b 3Σ+u state of H2 is isomorphic to that of the ground state. However, encompassing a genuine cage point rather than a cusp, it is associated primarily with the Fermi hole. Although the spatial extent of the cage evolves continuously with the internuclear separation R, it varies sharply around R=2.0 a.u., indicating a change in the dominant electronic configuration. Unlike in the case of the EF 1Σ+g state of H2, the electronic configurations that dominate at small and large internuclear separations share a single topology of the intracule density.