Electron Momentum Density of Hexagonal Magnesium Studied by Compton Scattering
Directional Compton profiles of single crystal of hcp magnesium have been measured with scattering vectors along the [10 10],  and  directions in reciprocal space (special directions ΓΜ, ΓΚ, ΓΑ) using high-energy (662 keV) gamma radiation from a 137Cs isotope source. The experimental data were compared with corresponding theoretical Korringa-Kohn-Rostoker (KKR) calculations. The directional difference profiles, both experimental (of medium resolution) and theoretical ones, show very small anisotropy of the electron momentum density in magnesium, 2-3 times lower than in zinc and cadmium single crystals, significantly lower than observed in cubic metals. This small directional effect is in good agreement with Compton 60-keV energy experiments and positron annihilation data presented by other authors.
Ludwik Dobrzynski and Krystyna Perzynska
M. Brancewicz et al., "Electron Momentum Density of Hexagonal Magnesium Studied by Compton Scattering ", Solid State Phenomena, Vol. 112, pp. 123-132, 2006