Computes and plot the electrons distribution in the ZB Brillouin zone

It uses the tight-binding model sp3s* where the parameters a from the following references:

-> for the III-V: KLIMECK et al, Superlattices and Microstructures, Vol. 27, No. 5/6, 2000

-> for Si: KLIMECK et al, Superlattices and Microstructures, Vol. 27, No. 2/3,2000

-> for Ge: VOGL et al, I. Phys. Chom. Solids Vol. 44, No. 5. pp. 365-378, 1983