The 2-dimensional angular correlation of positron annihilation radiation on a single crystal was measured for three projections. The spectra were subjected to the Van Citter-Gerhard deconvolution algorithm. The 3-dimensional p-space density ρ(p) was reconstructed using the Cormack method and a modified Fourier transform-based algorithm. The k-space density ρ(k) was then obtained by applying the 3D-LCW transformation to ρ(p). The Fermi surface was constructed by parameterising its volume with a geometrical model. The geometrical parameters were determined by means of a least-squares fit to the 2-dimensional LCW transformation, applied to two high symmetry projections.

Three-Dimensional Reconstruction of the Fermi Surface of LaB6. Biasini, M., Monge, M.A., Kontrym-Sznajd, G., Gemmi, M., Sato, N.: Materials Science Forum, 2001, 363-365, 582-4