Self-energies for the particle-hole propagator from Feynman-Dyson equations

摘要

Correlation -relaxation corrections to electronic transition energies are obtained through the self-energy fields for the particle-hole propagator. These objects lire generated from Feynman-Dyson like equations within the scenario of the superoperator algebra. A Hartree Fock reference stale and a partition of the operator space along with a particle conserving manifold arc used to recast the lower order perturbativc expressions for the self-energies. Correlated states are used to make explicit the appearance of higher order correction terms io the self-energy. It is explicitly shown that the present scheme leads to a proper classificatioo of the order of the c6ntribution from both the intrinsic ihteraction operator and the improved reference state.