Theoretical investigation of the single and double ionization spectra of M(CO)6, M=W

In this work, we study the single and double ionization spectra of the M(CO)6,with M =( W and Cr ) complexes by applying the four-component algebraic diagrammatic construction and Fock-space coupled cluster methods to extend earlier studies based on less demanding approaches. The computed single and double ionization potentials are in good agreement comparing with the available experimental results. The electronic structures of the cationic molecular systems are carefully investigated by computing accurately single and double ionization potentials. The final state characterization is relied on group theoretical considerations of the contributing orbitals and allowed for a clear assignment. Energy level diagrams show the effect of spin-orbit (SO) coupling starting from scalar relativistic results and for the heavy representative M(CO)6 with M =( W and Cr ) nonadditivity effects of the SO and electron correlation can be observed requiring a consistent treatment of both contributions.