Spontaneous symmetry breaking and electron correlation

Abstract

The Dyson equation and Green's function formalism map the problem of N electrons in the Born᎐Oppenheimer nuclear field into a one-electron Schrodinger equation problem in quantum chemistry. The mass operator contains the information about electron correlation, and the ground-state energy, electron affinity, and ionization energy of a molecular system. This pseudopotential approach is combined with the Ž . random-phase approximation RPA method to give a model with spontaneous symmetry breaking, where the relevant features are incorporated in a transparent way. An effective potential is developed consisting of a Hartree᎐Fock solution with auxiliary fields to probe for deformation instabilities. The model is then connected to a closely related perturbative propagator approach and linked with the configuration interaction formalism.