8 papers
From Full Dynamic to Pure Static: A Family of -Based Approximations
Pierre-François Loos, Johannes Tölle
We introduce a systematic hierarchy of one-body Green's function methods derived from the approximation, constructed by progressively reducing the dynamical content of the sel…
Connection between and Extended Coupled Cluster
Johannes Tölle, Marios-Petros Kitsaras, Andreas Irmler +2
Coupled-cluster (CC) theory and Green's function many-body perturbation theory (MBPT) have long evolved as distinct yet complementary frameworks for describing electronic correlati…
An Algebraic-Diagrammatic Construction for Vertex Corrections to the Self-Energy
Antoine Marie, Johannes Tölle, Pierre-François Loos
The approximation -- the second-order self-energy beyond -- is known to violate some fundamental analytic properties of the self-energy. In particular, its lack of posi…
Renormalization group approach to second-order Green's function theory
Joshua Krieger, Johannes Tölle
In this work, we introduce a new approach for constructing a renormalized and regularized Fock matrix for self-consistent field calculations. The scheme relies on second-order pert…
Analytic gradients based on a double-similarity transformation equation-of-motion coupled-cluster treatment
Marios-Petros Kitsaras, Johannes Tölle, Pierre-François Loos
The accurate prediction of ionization potentials (IPs) is central to understanding molecular reactivity, redox behavior, and spectroscopic properties. While vertical IPs can be acc…
Fully Analytic Nuclear Gradients for the Bethe--Salpeter Equation
Johannes Tölle, Marios-Petros Kitsaras, Pierre-François Loos
The Bethe-Salpeter equation (BSE) formalism, combined with the approximation for ionization energies and electron affinities, is emerging as an efficient and accurate method f…