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Updated: Aug 18, 2026

Ensemble Force Spectroscopy by Shear Forces
Published on: July 26, 2022
Spectroscopy of shear horizontal surface phonons by rotation-flip scattering of ortho-H2 molecules
Giorgio Benedek1, Franziska Traeger, J Peter Toennies
1Max-Planck-Institut für Dynamik und Selbstorganisation, Postfach 2853, D-37018 Göttingen, Germany.
Abstract:
Ortho-H2 molecules in the j=1 state are predicted, on the basis of a simple extension of the distorted wave approximation, to excite shear-horizontal (SH) polarized surface phonon modes, which are symmetry forbidden in inelastic He atom planar scattering. The symmetry breaking is provided by Deltam-rotational flip transitions which couple efficiently to the shear-horizontal modes. A confirmation is provided by the observation of SH surface phonons in phonon inelastic scattering of H2 from NaCl(001).
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