Abstract
The (100) surface core-level shifts of PbS, PbSe, PbTe, GeTe, and SnTe are calculated with use of a simple molecular model. For the unrelaxed surface, the calculated values are quite large and increase with the compound ionicity. This discrepancy with the available experimental result for PbS suggests a large (100) surface relaxation annealing the effects of the surface on core-level shifts.