Theoretical study of double-core-hole states in molecule

Abstract

We have calculated ionization potential (IP) for K-Shell single core hole (SCH) creation and double ionization potential (DIP) for K-Shell double core hole creation of XH_m-YH_n (X, Y = C, N, O, F, m,n=0-3), and C₆₀ within the framework of density functional theory (DFT). For these molecules, we estimated the relaxation energies (a measure of the electron density flow to the core-hole site) and the interatomic relaxation energies (a measure of the electron density flow to the two core-hole sites) from the calculated IPs and DIPs. For XH_m-YH_n, we find that the interatomic relaxation energy for the DCH states having two holes at X and Y atoms decreases with increasing in the bond order between X and Y. For DCH states having two holes at two carbon atoms in C₆₀, we find that the interatomic relaxation energy decreases with increasing in the hole-hole distance.