Energy Storage and Redistribution in Molecules

We characterize an isolated molecule by its compos~t~on, i.e. the number and types of atoms forming the molecule, its structure, i.e. the geometrical arrangement of the composite atoms with respect to each other, and its possible, i.e. quantum mechanically allowed, stationary energy states. Conceptually we separate the latter, being aware that this is an approximation, into electronic, vibrational and rotational states, including fine and hyperfine structure splittings. To be sure, there is an intimate relation between molecular structure and molecular energy states, in fact it is this relation we use, when we obtain structural information through spectroscopy, where we determine transitions between various stationary states of the molecule. The concepts above have proven extremely useful in chemistry and spectroscopy, however, the awareness of the limitations of these concepts has grown in recent years with the increasing recognition of (i) fluctional molecules, (ii) multiphoton absorption processes and (iii) influences due to the surroundings on "isolated" molecules.

Table of Contents:
Chemistry and Spectroscopy of Molecules at High Levels of Excitation.- Energy and Phase Randomization in Large Molecules as Probed by Laser Spectroscopy.- Intramolecular Processes in Isolated Polyatomic Molecules.- Pulse-Probe Measurements in Low-Temperature, Low-Pressure SF6.- Energy Scrambling in Molecules: Two Examples from Molecular Beam Spectroscopy.- The Photodissociation Dynamics of H2S and CF3NO.- Photofragment Spectroscopy of the NO2 Dissociation.- Preparation, Laser Spectroscopy and Predissociation of Alkali Dimers in Supersonic Nozzle Beams.- Quantum-State-Resolved Scattering of Lithium Hydride.- Excited States of Small Molecules - Collisional Quenching and Photodissociation.- Molecular Negative Ions.- The Hypothetical PH5 Molecule and its Reaction to PH3+H2.- Ab-Initio Studies of the Molecular Symmetry Breaking Problem: Low Lying States of CO2 and NO2.- Determination of Properties of Close-Lying Excited States of Olefins.- CEPA Calculations for Rotation Barriers about CC Double Bonds: Ethylene, Allene and Methylene-Cyclopropane.- Electron Correlation and the Mechanism of Atomic Autoionization.- The Symmetry Properties of Nonrigid Molecules.- Molecular Structure Derived from First-Principles Quantum Mechanics: Two Examples.- Kinematic and Dynamic Partitionings of the Energy; Coordinate and other Transformations.- The Calculation of Nuclear Motion Wave Functions in Rather Floppy Triatomic Molecules with CH2+ as an Example.- Potential Energy Surfaces and Some Problems of Energy Conversion in Molecular Collisions.- Derivative Coupling Elements in Electronically Adiabatic Representations and their Use in Scattering Calculations.- Dynamical Calculations on Transport Processes.- A Comment on Dynamical Chaos in Classical and Quantum Mechanical Hamiltonian Systems.- Theoretical Analysis of Experimental Probes of Dynamics of Intramolecular Vibrational Relaxation.- Some Kinetic and Spectroscopic Evidence on Intramolecular Relaxation Processes in Polyatomic Molecules.- Vibrational Energy Relaxation from CH-Stretching Modes of Small Molecules in the Liquid.- Irreversibility Questions in Chemistry, Quantum-Counting and Time-Delay.- Energy Scrambling out in the Continuum: Weyl's Theory and Predissociation.- Dynamical Equations for the Wigner Functions.- Vibrational Motion in the Regular and Chaotic Regimes, Classical and Quantum Mechanics.- Trajectory Calculations and Complex Collisions.- New Principles in Condensed Phase Chemistry.