Binding of an Electron by a Finite Fixed Dipole

In this work, it is demonstrated that a simple analytical expression, (A/R²) $$, where μ is the dipole moment, μ_cr is the critical dipole moment, and A and B are constants, accurately describes the binding energy of an electron in the field of a finite fixed dipole over a wide range of dipole moments. It is also demonstrated that this expression provides an accurate fit to the experimental electron binding energies for the dipole-bound anions of a series of phenoxy radicals. A simple extension of this expression is found to be applicable when the dipole model is extended to include short-range repulsion and polarization interactions.