Investigation of double photoionisation dynamics in molecules using coincidence techniques

The enormous progress that coincidence techniques have recently brought to the understanding of the double photoionisation process will be illustrated with a few examples. We shall especially insist on valence double photoionisation, presenting results on the spectroscopy of M(++) species, on the dynamics of the ejection of the 2 electrons, and on the dynamics of M(++) dissociation; finally, the interplay between electronic and nuclear dynamics will be stressed, as well as possible future routes to track this problem.