Spectroscopy of shear horizontal surface phonons by rotation-flip scattering of ortho-H2 molecules -: art. no. 086103

Ortho-H-2 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 H-2 from NaCl(001).