Imaging Polyatomic Molecules in Three Dimensions Using Molecular Frame Photoelectron Angular Distributions

We demonstrate a method for determining the full three-dimensional molecular-frame photoelectron\ud angular distribution in polyatomic molecules using methane as a prototype. Simultaneous double Auger\ud decay and subsequent dissociation allow measurement of the initial momentum vectors of the ionic\ud fragments and the photoelectron in coincidence, allowing full orientation by observing a three-ion decay\ud pathway, (H??, H??, CH??\ud 2 ). We find the striking result that at low photoelectron energies the molecule is\ud effectively imaged by the focusing of photoelectrons along bond direction