X-ray-absorption near-edge structure (XANES) data were collected for Zn in sphalerite (ZnS), and for Cu and Fe in chalcopyrite (${\mathrm{CuFeS}}_2$), where all three cations are in nearly identical coordination environments. The data have similar features, except near the edge, where the edge maximum decreases in amplitude, while a pre-edge feature appears and increases in amplitude from Zn to Cu to Fe. The pre-edge feature was previously assigned to a 1s-to-3d atomic transition for Cu and Fe in the chalcopyrite structure. XANES calculations were performed for all three edges. The multiple- and single-scattering contributions to the calculated edge spectra were scaled down to better fit the experimental data. The conclusions from the calculations indicate that the pre-edge feature in the experimental Cu- and Fe-edge data for chalcopyrite can be due to interference effects from the atomic structure surrounding the absorber, but cannot exclude the possibility that the pre-edge feature is due to atomic bound-state transitions of the absorber.

• Received 3 September 1991

DOI:https://doi.org/10.1103/PhysRevB.45.2648