The Perturbation Theory of Electron Correlation. I. Basic Rayleigh-Schrödinger Perturbation Theory

Abstract

This is the first of four articles describing the application of perturbation theory to the electron correlation problem in atoms and molecules. In this article, the basic formalism of Rayleigh-Schrodinger perturbation theory is presented in some detail. In the second article we describe the many-body perturbation theory paying particular attention to the formulation within the algebraic approximation, i. e. by using finite analytic basis sets. The use of relativistic many-body perturbation theory to describe both relativistic and correlation effects in atoms and molecules is described in the third article. In the final article, recent work on the concurrent computation many-body perturbation theory (ccMBPT) computer program, which is designed to exploit the power of multiprocessor supercomputers, is described. Throughout this work, references have been chosen to amplify the text and to indicate key papers and review articles. No attempt has been made to provide a comprehensive catalogue of the large and expanding literature of the perturbation approach to the problem of electron correlation.