ELECTRON-HYDROGEN FLUORIDE SCATTERING AT ULTRALOW ELECTRON ENERGIES -POSSIBLE ROLE OF DIPOLE-SUPPORTED STATES

A detailed experimental and theoretical study of the interaction of ve ry-low-energy electrons with the polar target HF is reported. This int eraction is investigated experimentally by measuring rate constants fo r ionization and state changing in collisions between K(np) Rydberg at oms with 90 less than or equal to n less than or equal to 400 and HF. The data are analyzed using the results of rotational close-coupling c alculations that include possible effects associated with dipole-suppo rted real or virtual states. A comparison of theory and experiment sug gests that low-energy-electron-HF scattering is strongly influenced by the presence of a dipole-supported virtual state with an energy, for J = 0, of similar to 1-1.5 meV. The present work points to the importa nce of dipole-supported states in electron-polar molecule scattering.