Compton profiles of B, B4C, BN, BeO, LiF and MgO

Compton profiles of polycrystalline boron (beta rhombohedral), boron carbide (B4C), BN (hexagonal) and BeO, and single crystal LiF and MgO were measured with MoKα x-radiation scattered through 118°. In all cases the measured Compton profiles are significantly broader than given by a super-position of Hartree-Fock neutral-free-atom electron momentum densities. Momentum wave functions for the solid are not available for comparison, but the broadenings of the valence electron momentum densities in these solids are typical of previous results. For LiF a superposition of Li+ and F− free-atom momentum densities was in much better agreement with the measurements than a superposition of neutral atoms. The anisotropy of the electron momentum density in LiF was small (<2%). For MgO a super-position of Mg++ and O− momentum densities was in much better agreement than a superposition of Mg°+O° momentum densities. The anisotropy in MgO was small (< 2%).