Electric-field-induced dissociation of heavy Rydberg ion-pair states*

A classical trajectory Monte Carlo approach is used to simulate the dissociation of H$^{+..}$F$^{-}$ and K$^{+..}$Cl$^{-}$ heavy-Rydberg ion pairs induced by a ramped electric field. Such field-induced dissociation is used experimentally to detect ion-pair states and analyze their binding energies. The simulations include the effects of the strong short-range repulsive interaction associated with ion-pair scattering. Their predictions are in good agreement with experimental data for Stark wavepackets probed by a ramped field, demonstrating that many of the characteristics of field-induced dissociation can be well described using a purely classical model. The data also show that states with a given value of principal quantum number (i.e., binding energy) can dissociate over a broad range of applied fields, the exact field being governed by the initial orbital angular momentum and orientation of the state.