  We present photoionization models accounting for both photoelectric and
resonant absorption. We demonstrate that resonance absorption lines are
detectable even in moderate resolution X-ray spectra of type 1 AGN. The spectra
transmitted by gas illuminated by the ionizing continua typical of flat X-ray
spectrum, broad optical emission line type 1 AGN, and steep X-ray spectrum,
narrow optical emission line type 1 AGN (NLSy1) are dramatically different. In
particolar, we find that both the absorption features seen in many Seyfert 1
galaxies between 0.7 and 1 keV and in several NLSy1 between 1 and 2 keV can be
explained by our model, without requiring relativistic outflowing velocities of
the gas.
