Orbital contributions to relaxation energies accompanying core ionizations in the series CO, COH+, HCO+ and H2CO

Abstract

Changes in binding and relaxation energies accompanying core ionizations are computed within the ΔSCF Hartree–Fock formalism for CO at the equilibrium geometry; CO at the geometries appropriate to COH⁺ and HCO⁺; COH⁺; HCO⁺(linear); HCO⁺(bent); HCO⁺(bent) with geometry appropriate to H₂CO; and H₂CO. Variations in relaxation energies along this series are discussed in terms of the individual valence orbital contributions to the total relaxation energies; it is found that such an analysis can provide considerable insight into the relationship between electronic structure and electronic reorganizations accompanying core ionization. Certain aspects of the energetics involved (protonation and hydrogenation in these systems) are also considered.