Showing papers by "Poul Jo published in 1972"
TL;DR: In this article, a self-consistent decoupling procedure analogous to the Hartree-Fock decoupled for the electron propagator was proposed for finding the particle-hole propagator.
Abstract: A formal scheme is developed for finding the particle‐hole propagator by means of a self‐consistent decoupling procedure analogous to the Hartree‐Fock decoupling for the electron propagator. The self‐consistency comes from a contour integration of the Fourier transform of the propagator, utilizing a method introduced by Coulson. The method yields oscillator strengths and excitation energies, as well as the two‐particle density matrix, which allows any one‐ or two‐particle operator expectation value to be evaluated. The stability of the scheme is discussed, and comparisons with other, related, approximations are made.
56 citations
TL;DR: By decoupling the equation of motion for the two-particle Green's function, a self-consistent scheme for describing particlehole excitations was developed as discussed by the authors, which is applied to the π-electron systems of ethylene, butadiene, and benzene.
Abstract: By decoupling the equation of motion for the two‐particle Green's function, a self‐consistent scheme for describing particle‐hole excitations is developed. The self‐consistent propagator is brought into a form which easily yields excitation energies and oscillator strengths. The method is applied to the π‐electron systems of ethylene, butadiene, and benzene. Comparison is made with results obtained in the time‐dependent Hartree‐Fock approximation and related schemes. The problems concerning particle number conservation in these methods are discussed.
38 citations