Quantum mechanics is the fundamental theory of matter on the microscopic scale. Thanks to conceptual advances and progress in computer technology, its application to the study of atomic and molecular systems, which is of relevance to chemistry, physics, biology, and materials science, is a rapidly developing research area. Advances in the Theory of Atomic and Molecular Systems is a two-volume collection of 33 papers that define its leading edge: they present recent theoretical and computational developments that provide new insights into the structure, properties, and behavior of a variety of atomic and molecular systems. These papers are a selection of some of the most out-standing presentations made at the 13th International Workshop on Quantum Systems in Chemistry and Physics (QSCP-XIII), held at Lansing, Michigan, USA, in July 2008. Since the QSCP-XIII workshop was coordinated with the 6th Congress of the International Society for Theoretical Chemical Physics (ISTCP-VI) held at Vancouver, British Columbia, Canada, in July 2008 as well, three of the 33 papers included in the present two volumes have been written by ISTCP-VI participants.

"Advances in the Theory of Atomic and Molecular Systems, is a collection of contributions presenting recent theoretical and computational developments that provide new insights into the structure, properties, and behavior of a variety of atomic and molecular systems. This volume (subtitled "Dynamics, Spectroscopy, Clusters, and Nanostructures") deals with the topics of "Quantum Dynamics and Spectroscopy", "Complexes and Clusters", and "Nanostructures and Complex Systems".This volume is an invaluable resource for faculty, graduate students, and researchers interested in theoretical and computational chemistry and physics, physical chemistry and chemical physics, molecular spectroscopy, and related areas of science and engineering."

Quantum Dynamics and Spectroscopy.- Quantum Theory in Terms of Cumulant Variables.- Nonclassical Phase Space Jumps and Optimal Spawning.- On the Differential Cross Sections in Complex-Forming Atom-Diatom Reactive Collisions.- Shared Memory Parallelization of the Multiconfiguration Time-Dependent Hartree Method and Application to the Dynamics and Spectroscopy of the Protonated Water Dimer.- Structural Properties and Torsional Dynamics of Peroxides and Persulfides.- Theoretical Spectroscopy of Inner-Shell Electronic Processes and Photochemistry of Fluorescent Molecules.- Electron-?-Nuclear Spectroscopy of Atoms and Molecules and Chemical Bond Effect on the ?-Decay Parameters.- Complexes and Clusters.- Quantum Chemical Approach to Interatomic Decay Rates in Clusters.- Spectroscopy of Atoms in Liquid Helium Environment: A Theoretical Perspective.- Level-Structure and Magnetic Properties from One-Electron Atoms to Clusters with Delocalized Electronic Orbitals: Shell Models for Alkali Trimers.- Nanostructures and Complex Systems.- Influence of the Level of Protonation on the Geometry and the Electronic Structure of Emeraldine Oligomers.- Quantum Mechanical Examination of Optical Absorption Spectra of Silver Nanorod Dimers.- On the Electronic Spectra of a Molecular Bridge Under Non-Equilibrium Electric Potential Conditions.