  We have investigated the imaginary part of the dielectric function
Im(epsilon) of the (113) 3x2 ADI reconstructed surface of silicon. The
calculations have been performed for a periodic slab within the plane-wave
pseudopotential approach to the density-functional theory. The three diagonal
components of Im(epsilon) have been derived from the momentum matrix elements
within the independent particle random phase approximation (IPRPA). In this
article, the importance of the k-point convergence is figured out by inspecting
k-point resolved spectra.
