Theoretical study on decay of molecular double core-hole state

Molecular double core-hole (DCH) state, having two core-hole vacancies in its K-shell orbital(s), has attracted attention in recent experiments using X-ray free electron laser and synchrotron radiation with multi-electron coincidence technique. From theoretical point of view, we describe basic properties of ionization energy of molecular DCH state, including dependence of the ionization energies on molecular environments. Decays of molecular DCH state by Auger electron emission and X-ray emission will be discussed, using CH4 and CO as representative examples. (C) 2013 Elsevier B.V. All rights reserved.