Abstract: We present the X?ray properties of a large, optically selected sample of quasars from a cross?correlation of the SDSS DR5 quasar catalogue and the X?ray serendipitous source catalogue 2XMMi. We consider the dependence of photon index on X?ray luminosity and redshift. We find evidence for a correlation of photon index and redshift (decreasing photon indices for higher red?shift sources) and propose that this may be due to a Compton reflection component being redshifted into the XMM?Newton observed energy band. We show that this apparent trend can be removed when the spectra are analysed over a reduced range that would exclude any contribution from such a reflection component.

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