The isotropic Compton profile of BeO has been measured using a γ-ray Compton spectrometer which employs a 5 Ci annular Am241 source. The measurement is compared with the theoretical HF-LCAO Compton profile published by Lichanot et al. The measurement has also been compared with our calculations based on the RFA model employing different ionic wavefunctions. It is seen that the experimental Compton profile is in very good agreement with the HF-LCAO calculations. To determine the nature of bonding, equal-valence-electron-density Compton profile of BeO has been compared with that of the isovalent compound MgO. It is observed that the bonding in BeO is partially covalent and less ionic than MgO in agreement with the conclusions of the HF-LCAO calculation.

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The empirical pseudopotential method has been applied to study electronic band structures of BeTe and ZnTe. The band‐structure calculations are performed to study the electron momentum density distribution also in the two semiconductors. The electron momentum distribution is studied in terms of Compton profiles computed along [100], [110], [111], [210], [211] and the [221] directions. The autocorrelation functions have also been computed along the principal crystallographic directions. The band‐by‐band decomposition of autocorrelation functions and the directional Compton profiles are presented. The results are interpreted in terms of band structure. The spherically averaged Compton profile of ZnTe is compared with the available experimental data. On the basis of theoretical anisotropies in the Compton profiles and autocorrelations, bands, bonds and momentum density build up in BeTe and ZnTe semiconductors are discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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