Generalised Nonorthogonal Matrix Elements: Unifying Wick's Theorem and the Slater-Condon Rules

no code implementations • 26 Jan 2021 • Hugh G. A. Burton

Our approach creates a universal methodology for evaluating any nonorthogonal matrix element and allows Wick's theorem and the generalised Slater-Condon rules to be unified for the first time.

Chemical Physics

Perturbation Theory in the Complex Plane: Exceptional Points and Where to Find Them

no code implementations • 7 Dec 2020 • Antoine Marie, Hugh G. A. Burton, Pierre-François Loos

We explore the non-Hermitian extension of quantum chemistry in the complex plane and its link with perturbation theory.

Chemical Physics Strongly Correlated Electrons Computational Physics Quantum Physics