Quantum-Resolved Gas-Surface Scattering: NH3 from Au (111)

Abstract

We have measured angular, velocity, and quantum-state distributions for ammonia molecules scattered from a gold (111) single crystal for a number of surface temperatures and incident beam energies. A molecular beam source produces a well-collimated, rotationally cold (~15 K) beam of NH3 molecules with a narrow dispersion of translational energy (~10%). The molecular beam impinges on an atomically clean, single crystal of gold (111) and the scattered NH3 is detected in a quantum-resolved manner using two-photon resonant, three-photon ionization [1].