Molecular self-diffraction on a surface: Inversion symmetry changes in scattering of state-selected ND3 on graphite (0001).

Abstract

State-selected molecular beams of ${\mathrm{ND}}_{3}$ in antisymmetric inversion states (\ensuremath{\Vert}JKM〉\ensuremath{\Vert}inversion〉=\ensuremath{\Vert}111〉\ensuremath{\Vert}-〉 or \ensuremath{\Vert}222〉\ensuremath{\Vert}-〉+\ensuremath{\Vert}333〉\ensuremath{\Vert}-〉) are scattered on a graphite (0001) surface. A preponderance of symmetric inversion states, \ensuremath{\Vert}+〉, is observed in the directly scattered molecules. The observed effect is an interference between the ``left,'' C-${\mathrm{ND}}_{3}$, and ``right,'' C-${\mathrm{D}}_{3}$N, inversion configurations of a single molecule on a surface potential. This molecular self-diffraction on a surface is related to the orientational asymmetry in the molecule-surface interaction.