Fig. 2: Born-Oppenheimer potential energy curves resulting from the electron-ground state scattering.
From: Exploring the vibrational series of pure trilobite Rydberg molecules
The energy zero is the asymptotic pair state energy of a 22F7/2 state and an F = 1 ground state atom. The three labeled trilobite potentials result from different couplings of the spins s1, s2, and I. While the curves labeled F = 1 and F = 2 exhibit triplet scattering, the mixed curve has a mixture of singlet and triplet scattering, which in turn means a superposition of F = 1 and F = 2 in the ground state atom. The kink at about 970 a0 is due to the semi-classical calculation of the electron momentum k. Insets: Electronic probability density for the trilobite molecule shown at three different internuclear distances. At about 780 a0 the trilobite curves are crossed by the butterfly potentials, which result from a shape resonance in the p-wave scattering. The leftmost inset shows the electronic structure of a butterfly molecule.
