Valence Bond Methods Theory and Applications [Paperback]

This book focuses on ab initio valence bond theory.This book focuses on ab initio valence bond theory, one of two commonly used methods in molecular quantum mechanics. The book is split into two parts; part one discusses the necessary theory, whilst part two works through a series of case studies. Throughout the book reference is made to the CRUNCH computer program which is a widely available program for molecular structure calculations. The book is of primary interest to researchers working on molecular electronic theory and computation in chemistry and chemical physics.This book focuses on ab initio valence bond theory, one of two commonly used methods in molecular quantum mechanics. The book is split into two parts; part one discusses the necessary theory, whilst part two works through a series of case studies. Throughout the book reference is made to the CRUNCH computer program which is a widely available program for molecular structure calculations. The book is of primary interest to researchers working on molecular electronic theory and computation in chemistry and chemical physics.Valence bond theory is one of two commonly used methods in molecular quantum mechanics; the other is molecular orbital theory. This book focuses on the first of these methods: ab initio valence bond theory. The book is split into two parts. Part I gives simple examples of two-electron calculations and the necessary theory to extend these to larger systems. Part II gives a set of case studies of related molecule sets designed to show the nature of the valence bond description of molecular structure. The book is of primary interest to researchers and students working on electronic theory and computation in chemistry and chemical physics.Preface; Part I. Theory and Two-Electron Systems: 1. Introduction; 2. H2 and localised orbitals; 3. H2 and delocalised orbitals; 4. Three electrons in doublet states; 5. Advanced methods for larger molecules; 6. Spatial symmetry; 7. Varieties of valelc`