Relaxed electric dipole moments of polar molecules interacting with a slow positron: H2O and CH3X (X=F, Cl, Br)

Abstract

The variation in the electric dipole moments of H2O, CH3F, CH3Cl and CH3Br as their geometries relax due to interaction with a positron is evaluated. The results are in good agreement with a recently observed empirical dependence of the positron binding energy on molecular properties (Danielson et al 2009 J. Phys. B: At. Mol. Opt. Phys. 42 235203). For binding energies larger than 100 meV relaxation could alter significantly the analysis of the binding, but it is in the prospect of generating effective potentials for positron scattering by molecules that the effect can be more important.