Sitz, Greg Orman2011-04-252017-05-112011-04-252017-05-112002-05http://hdl.handle.net/2152/11014textThe effects of rotational alignment in surface scattering phenomena are studied. Alignment means a spatial preference for the plane of rotation. Specifically, changes in the reflection probability for H2 reaction with Pd(111) were studied for different molecular rotational alignments (helicopters vs. cartwheelers) and different incident translational energies. Experimentally, molecules were prepared with well-defined, non-statistical alignments using a linearly polarized laser before interaction with the surface. After scattering, the molecules were probed with another laser to determine their internal state. We found that the reflectivity of helicopter molecules was less than that of cartwheeler molecules. This effect increased with increasing incident energy. The result is interpreted as meaning that helicopters are more likely to dissociate than to scatter. The results are further evidence of steric forces in the H2/Pd interaction.electronicengCopyright is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works.Scattering (Physics)Molecular rotationDissociationRestricted