J. Phys. IV France 7 (1997) C2-283-C2-284
The Chemical Bonding in Crystals with Chalcopyrite StructureA.A. Lavrentyev1, I.Ya. Nikiforov2 and B.V. Gabrelian1
1 Department of Physics, Don State Technical University, Gagarin sq. 1, Rostov-on-Don 344010, Russia
2 Department of Physics, Don State Technical University, Gagarin sq. 1, Rostov-on-Don 344010 Russia
Experimentally with x-ray spectroscopy method and theoretically using the cluster approach of the local coherent potential method the particularities of chemical bonds of the semiconductors AgGaS2, AgInS2, CuGaS2, CuInS2 have been investigated. The fluorescent x-ray emission K-bands and the absorption K-spectra (XANES) of sulphur in the compounds investigated were obtained with resolution 0.2 eV. For upper part of the valence bands the electron structure is due to the occupied d-states of the noble metal (Ag, Cu), which mix with the delocalized p-states of S. The significant mixture of these states shows the strong covalent bond of S atom with noble metal atom.'The three maxima splitting of these states confirms the resonance character of the interaction of these atoms. The similarity of results for both chalcopyrite and zinc-blend stuctures proves, that the short-range ordering determines the electronic energy structure of these tetrahedral semiconductors.
© EDP Sciences 1997