Classical theory
Experimentally it has been observed that when heavy atoms such as Ar are scattered from metal surfaces, their angular distribution is a double peaked one. It has been well understood that the two peaks are related to the classical rainbow angles. However a complete theory which accounts both for the rainbow scattering as well as for phonon induced effects has been lacking. Using a classical Wigner approach we have recently derived a theory which accounts well for the structure and at the same time for surface temperature effects [12-14]. An interesting discovery is the existence of energy loss rainbows [15]. At present we are pursuing on the fly molecular dynamics methods for surface scattering.
Theory of heavy atom quantum diffraction
Quantum diffraction of heavy atoms has been observed in many instances in the past, albeit without a deep theoretical analysis. We have recently showed that the collimation of the incident beam can lead to diffraction patterns also for heavy particles scattered from surfaces [16]. We are pursuing this theory in order to understand whether suitable collimation can be a useful source for coherent control of scattering of atoms and molecules from surfaces.