Role of the Electron-Dipole Interaction in Photodetachment Angular Distributions.

The importance of including long-range electron-molecule interactions in treatments of photodetachment and/or photoionization is demonstrated. A combined experimental and computational study of CN- detachment is presented in which near threshold anisotropy parameters (β) are measured via photoelectron imaging. Calculated β values, based on an EOM-IP-CCSD/aug-cc-pVTZ Dyson orbital, are obtained using free-particle and point dipole models. The results demonstrate the influence of the molecular dipole moment in the detachment process and provide an explanation of the recently reported near threshold behavior of the overall photodetachment cross section in CN- detachment.