Recursive scheme for order-by-order many-body perturbation theory

Abstract
The coupled-cluster method is used to recursively organize the calculations for nondegenerate order-by-order many-body perturbation theory. Application to correlation energy with Hartree-Fock zeroth-order state is presented. Commutator algebra is efficiently handled with the contraction theorem. When compared to standard diagrammatic methods, considerable simplifications are found beyond third order.