Positron binding in chloroethenes: Modeling positron-electron correlation-polarization potentials for molecular calculations

Abstract

Positron binding energies and annihilation spectra are calculated using the positron-electron correlation-polarization potential model for a series of six chloroethene molecules. From detailed analysis of the positron densities and positron-molecule interactions, it was found that the positron is attracted by both the potential well around the negative end of the dipole moment and the π electrons of the C=C double bond. The positron annihilation spectra were simulated using the Feshbach resonance widths, which can be calculated from the couplings between the positron motion and vibrational motion. The importance of π electrons in positron binding is discussed in terms of the calculated resonance widths.