  Based on a combination of cluster dynamical mean field theory (DMFT) and
density functional calculations, we calculated the angle-integrated spectral
density in the layered $s=1/2$ quantum magnet TiOCl. The agreement with recent
photoemission and oxygen K-edge X-ray absorption spectroscopy experiments is
found to be good. Th e improvement achieved with this calculation with respect
to previous single-site DMFT calculations is an indication of the correlated
nature and low-dimensionality of TiOCl.
