Investigating the Molecular Time Domain: Interatomic Coulombic Decay

Interatomic (or intermolecular) Coulombic Decay (ICD) has become an extensively studied atomic decay process during the last 10 years. In ICD an excited atom or molecule deexcites by transferring its excitation energy to a loosely bound atomic neighbor and leads to the emis-sion of an electron from that neighbor. Originally proposed by Cederbaum et al. it was first experimentally observed by two groups using different techniques. Since that time a wealth of experimental and theoretical studies have shown that ICD is a rather common decay path in nature, as it occurs almost everywhere in loosely bound matter. The talk will give an introduction on ICD and show experimental investigations separating different contributions to the ICD transition matrix element. An introduction to the concept of “PCI-streaking” to experimentally access the molecular time domain will be presented and two examples, namely the investigation of the nuclear dynamics that occur during Interatomic Coulombic Decay (ICD) in He dimers and NeKr dimers, will be shown. Furthermore results on the decay of carbon monoxide molecules after C-K-ionization will be presented revealing the future applicability of this novel experimental method. The final part of the talk will give a view on possible future applications of ICD and demonstrate further ways of retrieving information on the decay time.