Vibrational Dynamics Of Molecules

Vibrational Dynamics of Molecules represents the definitive concise text on the cutting-edge field of vibrational molecular chemistry. The chapter contributors are a Who's Who of world leaders in the field. The editor, Joel Bowman, is widely considered as one of the founding fathers of theoretical reaction dynamics. The included topics span the field, from fundamental theory such as collocation methods and vibrational CI methods, to interesting applications such as astrochemistry, supramolecular systems and virtual computational spectroscopy. This is a useful reference for theoretical chemists, spectroscopists, physicists, undergraduate and graduate students, lecturers and software developers.

Remarkable developments in the spectroscopy field regarding ultrashort pulse generation have led to the possibility of producing light pulses ranging from 50 to5 fs and frequency tunable from the near infrared to the ultraviolet range. Such pulses enable us to follow the coupling of vibrational motion to the electronic transitions in molecules and

The book reviews the results of vibration-rotational spectroscopy of molecules obtained recently by combining modern computational methods of quantum chemistry with the new techniques of high-resolution rotational and vibration-rotational spectroscopy. It shows for example that the tunneling vibration-rotational spectroscopy of the van der Waals complexes provides a new look at intermolecular forces while the high precision and sensitivity of the submillimeter-wave and Fourier transform microwave spectroscopy make it possible to study complex rotational spectra of molecules in excited vibrational states. New results of high level ab initio quantum chemical computations of vibrational and rotational energy levels and dipole moment functions of unusual molecules will be discussed together with the recent discovery of clustering of energy levels in asymmetric tops. Group theoretical analysis of floppy molecules, especially the tunneling effects in nonrigid molecules, will also be discussed.

Since the first stimulated emission pumping (SEP) experiments more than a decade ago, this technique has proven powerful for studying vibrationally excited molecules. SEP is now widely used by increasing numbers of research groups to investigate fundamental problems in spectroscopy, intramolecular dynamics, intermolecular interactions, and even reactions. SEP provides rotationally pre-selected spectra of vibrationally highly excited molecules undergoing large amplitude motions. A unique feature of SEP is the ability to access systematically a wide variety of extreme excitations localized in various parts of a molecule, and to prepare populations in specific, high vibrational levels. SEP has made it possible to ask and answer specific questions about intramolecular vibrational redistribution and the role of vibrational excitation in chemical reactions.

This book focuses on current applications of molecular quantum dynamics. Examples from all main subjects in the field, presented by the internationally renowned experts, illustrate the importance of the domain. Recent success in helping to understand experimental observations in fields like heterogeneous catalysis, photochemistry, reactive scattering, optical spectroscopy, or femto- and attosecond chemistry and spectroscopy underline that nuclear quantum mechanical effects affect many areas of chemical and physical research. In contrast to standard quantum chemistry calculations, where the nuclei are treated classically, molecular quantum dynamics can cover quantum mechanical effects in their motion. Many examples, ranging from fundamental to applied problems, are known today that are impacted by nuclear quantum mechanical effects, including phenomena like tunneling, zero point energy effects, or non-adiabatic transitions. Being important to correctly understand many observations in chemical, organic and biological systems, or for the understanding of molecular spectroscopy, the range of applications covered in this book comprises broad areas of science: from astrophysics and the physics and chemistry of the atmosphere, over elementary processes in chemistry, to biological processes (such as the first steps of photosynthesis or vision). Nevertheless, many researchers refrain from entering this domain. The book "Molecular Quantum Dynamics" offers them an accessible introduction. Although the calculation of large systems still presents a challenge - despite the considerable power of modern computers - new strategies have been developed to extend the studies to systems of increasing size. Such strategies are presented after a brief overview of the historical background. Strong emphasis is put on an educational presentation of the fundamental concepts, so that the reader can inform himself about the most important concepts, like eigenstates, wave packets, quantum mechanical resonances, entanglement, etc. The chosen examples highlight that high-level experiments and theory need to work closely together. This book thus is a must-read both for researchers working experimentally or theoretically in the concerned fields, and generally for anyone interested in the exciting world of molecular quantum dynamics.

This volume focuses on molecular clusters, bound by van der Waals interactions and hydrogen bonds. Twelve chapters review a wide range of recent theoretical and experimental advances in the areas of cluster vibrations, spectroscopy, and reaction dynamics. The authors are leading experts, who have made significant contributions to these topics. The first chapter describes exciting results and new insights in the solvent effects on the short-time photo fragmentation dynamics of small molecules, obtained by combining heteroclusters with femtosecond laser excitation. The second is on theoretical work on effects of single solvent (argon) atom on the photodissociation dynamics of the solute H2O molecule. The next two chapters cover experimental and theoretical aspects of the energetics and vibrations of small clusters. Chapter 5 describes diffusion quantum Monte Carlo calculations and non additive three-body potential terms in molecular clusters. The next six chapters deal with hydrogen-bonded clusters, reflecting the ubiquity and importance of hydrogen-bonded networks. The final chapter provides the microscopic theory of the dynamics and spectroscopy of doped helium cluster, highly quantum systems whose unusual properties have been studied extensively in the past couple of years.

Molecular Spectroscopy and Quantum Dynamics, an exciting new work edited by Professors Martin Quack and Roberto Marquardt, contains comprehensive information on the current state-of-the-art experimental and theoretical methods and techniques used to unravel ultra-fast phenomena in atoms, molecules and condensed matter, along with future perspectives on the field. Contains new insights into the quantum dynamics and spectroscopy of electronic and nuclear motion Presents the most recent developments in the detection and interpretation of ultra-fast phenomena Includes a discussion of the importance of these phenomena for the understanding of chemical reaction dynamics and kinetics in relation to molecular spectra and structure

Covers both molecular and reaction dynamics. The work presents important theroetical and computational approaches to the study of energy transfer within and between molecules, discussing the application of these approaches to problems of experimental interest. It also describes time-dependent and time-independent methods, variational and perturbative techniques, iterative and direct approaches, and methods based upon the use of physical grids of finite sets of basic function.