Atomic theory generally provides a good description of the photoeffect, including absorption, emission and scattering, over a broad range of energies from the far UV to X-ray wavelengths. However, solid state effects lead to corrections, typically about 10-20% or more in these spectra, particularly near transition thresholds. Here, we discuss such solid state corrections using a relativistic, real-space Green's function (RSGF) approach. In this approach both the real and imaginary parts of the X-ray scattering amplitude are calculated simultaneously in the complex energy plane, which simplifies the treatment of finite-temperature and experimental resolution. The approach also takes into account final state effects, including many body, core-hole effects, lifetime, and Debye-Waller factors. Several prototypical examples are given to illustrate the these effects.