Dynamical quantum filtering in the scattering dynamics of H2on Cu(001)

We investigate and discuss the effects of dynamical quantum filtering on the scattering dynamics of H2 on Cu(001); we perform coupled-channel calculations, including all six degrees of freedom of H2, on an ab initio potential energy surface. Our results show that cartwheel-like rotating H2 molecules (with their angular momentum vectors j predominantly oriented parallel to the surface) exhibit strong specular scattering on Cu(001), while helicopter-like rotating H2 molecules (with their angular momentum vectors j predominantly oriented perpendicular to the surface) exhibit off-specular scattering on Cu(001). These results indicate that we can obtain H2 molecules with aligned angular momentum vectors j, by scattering them from solid surfaces.