Same but different: Dipole-stabilized shape resonances in CuF- and AgF-
Electron attachment to closed-shell molecules is a gateway to various important processes in the gas and condensed phases. The properties of an electron-attached state, such as its energy and lifetime as well as the character of the molecular orbital to which the electron is attached, determine the fate of the anion. In this experimental and theoretical study of copper and silver fluoride anions, we introduce new types of resonances. Abrupt changes in photoelectron angular distributions point to the existence of autodetaching states. Equation-of-motion coupled-cluster singles and doubles calculations augmented by a complex absorbing potential identify some of these states as sigma and pi dipole-stabilized resonances, a new type of shape resonance. In addition, these molecules support valence and dipole-bound states and a sigma resonance of charge-transfer character. By featuring five different types of anionic states, these diatomics provide a vehicle for studying fundamental properties of anions and for validating new theoretical approaches for metastable states.