Determination of Compton profiles at solid surfaces from first-principles calculations

Projected momentum distributions of electrons, i.e., Compton profiles above the topmost atomic layer have recently become experimentally accessible by kinetic electron emission in grazing-incidence scattering of atoms at atomically flat single crystal metal surfaces. Subthreshold emission by slow projectiles was shown to be sensitive to high-momentum components of the local Compton profile near the surface. We present a method to extract momentum distribution, Compton profiles, and Wigner and Husimi phase space distributions from ab initio density-functional calculations of electronic structure. An application for such distributions to scattering experiments is discussed.