Model potential based estimation of positron bound states with polar molecules

Abstract: Positron forming a bound state with molecules is an area of meticulous research and remains open to simpler techniques for estimating the binding energy. Correlation between the incoming positron and the molecular electrons plays a crucial role even for polar molecules, where binding is also possible at the static-potential level. In this work, we have used a model correlation potential, which accounts for the virtual positronium formation, in the single-center expansion scattering calculations for polar oxygen-containing molecules. The thus determined S-matrix is continued into the complex momentum plane by fitting it to the Pade approximant. The positron bound state is estimated using the calculated pole position of the S-matrix. The results, compared with the latest experimental and ab initio findings, look quite promising.