Electron capture and scaling anomaly in polar molecules

Abstract We present a new analysis of the electron capture mechanism in polar molecules, based on von Neumann's theory of self-adjoint extensions. Our analysis suggests that it is theoretically possible for polar molecules to form bound states with electrons, even with dipole moments smaller than the critical value D 0 = 1.63 × 10 −18 esu cm . We argue that the quantum mechanical scaling anomaly is responsible for the formation of these bound states.