The Electron-Phonon Interaction at Vicinal Metal Surfaces Measured with Helium Atom Scattering.

Recently, it was demonstrated that inelastic helium atom scattering from conducting surfaces provides a direct measurement of the surface electron-phonon coupling constant (mass enhancement factor ) via the temperature or the incident wave vector dependence of the Debye-Waller exponent. Here, previous published as well as unpublished helium atom scattering diffraction data from the vicinal surfaces of copper (Cu(11α), with α = 3, 5, 7) and aluminum (Al(221) and Al(332)) were analyzed to determine . The results suggested an enhancement with respect to the corresponding data for the low-index surfaces (111) and (001) above the roughening transition temperature.

A semiempirical potential for alkali halide diatoms with damped interactions I. Rittner potential.

A new semiempirical potential is described for the ground state XΣ of the alkali halide diatoms. The model potential is the first to account for the damping of all the electrostatic and induction potential terms as well as of the long-range dispersion potential. Accordingly, the potential does not have a negative singularity at vanishingly small internuclear distances and is the first Rittner-type model with a realistic dependence of the repulsion at short distances.