New results on X-ray models and atomic data

We discuss the most recent developments of the spectral analysis package SPEX. We report on the progress made in updating the atomic data that are used in the spectroscopic code. We also present a set of spectral models that are used for the analysis of high-resolution X-ray spectra of photo-ionized plasmas such as occur in active galactic nuclei. These models include absorption line spectroscopy of photoionized layers. The importance and diagnostic power of inner-shell transitions is shown. We illustrate our results with several examples of observed spectra obtained with the XMM-Newton and Chandra grating spectrometers.