APW-Xα Compton profiles in crystalline rare gases

Augmented Plane Wave, local exchange (APW-Xα) one-electron wave functions have been used to calculate Compton profiles for crystalline Ne at three different lattice constants for two values of the local exchange parameter. Some results for Ar, Kr, and Xe are also presented. The impulse approximation is used. The crystalline calculations are little different from the isolated atom results. A variety of difficulties, primarily due to the energy-dependent nature of the APW basis, are explored. A translational symmetry restriction that is particularly severe for APW calculations of Compton profiles is studied. In all, it is concluded that the APW scheme is ill-suited to the computation of the sort of non-energy quantity represented by a Compton profile.