Electronic States of Molecules and Atom Clusters

Foundations and Prospects of Semiempirical Methods

von G. Del Re, J. Serre, G. Berthier

192 Seiten, Taschenbuch

Kurzbeschreibung des Verlags

1. Models and concepts in molecular theory.- 1.1 Scope of the quantum theory of molecules.- 1.2 Born Oppenheimer states.- 1.3 Computational and interpretational problems.- 1.4 Rôle and limitations of simplified models.- 1.5 Simplified models and model Hamiltonians.- 1.6 Atoms in molecules and electronegativities.- 1.7 A conclusion: Models and the Plague of Non-observables.- 2. Mathematical foundations.- 2.1 Mathematical construction of many-electron models from an orbital basis.- 2.2 Model Hamiltonians.- 2.3 Matrix formalism. Inclusion of overlap.- 2.4 The spectral decomposition of the Hamiltonian and effective potentials.- 3. One-electron schemes.- 3.1 Hückel-type methods.- 3.2 A 'naive' method for ? electrons.- 3.3 The Hückel method for all valence-electrons: The tight binding (TB) approach of solid-state physics.- 3.4 All-valence-electron treatments: The extended Hückel theory (EHT).- 4. Simplified SCF one-electron schemes and beyond.- 4.1 The SCF Hamiltonian.- 4.2 Construction of non-SCF Hamiltonians.- 4.3 Many-electron models and their SCF version.- 4.4 Methods with iterative determination of atomic parameters.- 4.6 A general form of all valence SCF methods: The SCF extended-Hückel method.- 4.7 Beyond one-electron schemes. Correlation, PCILO method excited states.- 4.8 A case study in semiempirical computations: Molecular force fields.- 4.9 Limitations of semiempirical and limited-basis methods: The N2O4 molecule.- 5. The basis problem.- 5.1 MVAO basis.- 5.2 Non-orthogonality.- 5.3 General orbital bases.- 5.4 ?-Electron models and the ?-? separation.- 5.5 Basis problem in solid-state physics.- 5.6 Metal-metal bond and the X? method.- 5.7 Reliability of computations and choice of the orbital basis.- 5.8 A comment on the use of group theory incalculations on molecules and aggregates of atoms.

• Reihe: Lecture Notes in Chemistry
• Themen: Mathematik und Naturwissenschaften Chemie Physikalische Chemie Quanten- und theoretische Chemie
• ISBN: 9783540097389
• Sprache: Englisch
• Erscheinungsdatum: 01.09.1980
• Größe: 244 x 170 mm
• Verlag: Springer