Special directions in momentum space. I. Cubic symmetries

Some new sets of special directions (SDs) in the Brillouin zone for cubic structures are presented. They allow for construction in the reciprocal space of anisotropic quantities, having Γ₁ symmetry, from knowledge of such quantities along a limited number of SDs. These SDs also define which spectra, measured, for example, in Compton scattering experiments, are the most efficient for reconstructing three-dimensional densities from their one-dimensional projections. The new SDs are compared with results obtained by other authors.