The Tunnel Effect in Chemistry


Book Description

The suggestion that quantum-mechanical tunnelling might be a significant factor in some chemical reactions was first made fifty years ago by Hund, very soon after the principles of wave mechanics had been established by de Broglie, Schrodinger and Heisenberg, and similar ideas were put forward during the following thirty years by a number of authors. It was realised from the beginning that such effects would be particularly prominent in reactions involving the movement of protons or hydrogen atoms, and both theoretical and experimental work received a powerful stimulus in the discovery of deuterium in 1932. During the last twenty years theoretical predictions about the tunnel effect have been supported by an increasing body of experimental evidence, derived especially from studies of hydrogen isotope effects. The present book presents an attempt to summarize this evidence and to indicate the main lines of the basic theory. Details of mathematical manipu lation are restricted mainly to Chapter 2 and the Appendices, and many readers may prefer to confine themselves to the results obtained. The main emphasis has been on the kinetics of chemical reactions involving the transfer of protons, hydrogen atoms or hydride ions, although Chapter 6 gives an account of the role of the tunnel effect in molecular spectra, and Chapter 7 makes some mention of tunnelling in solid state phenomena, biological processes and the electrolytic discharge of hydrogen. Only passing references have been made to tunnelling by electrons.




Tunneling Phenomena in Chemical Physics


Book Description

Surveys the contemporary concepts and theoretical and experimental results of tunneling processes. Examines from a unified viewpoint not only chemical reactions but also other physical physicochemical and biological phenomena in which the tunneling effect is of great importance. Covers the general ideas of tunneling, the low temperature chemical reactions that manifest tunneling mechanisms, tunneling effects in amorphous materials, quantum diffusion and surface phenomena in quantum crystals, hopping diffusion and tunneling scavenging of electrons, and tunneling effects in biological systems.




Tunnelling in Molecules


Book Description

Nuclear Quantum Effects from Bio to Physical Chemistry




Electron Tunneling in Chemistry


Book Description

In Volume 30, an attempt is made to consider comprehensively both theoretical and experimental data that have been obtained to date on electron tunneling reactions involving chemical compounds of various classes, and to discuss the role played by these reactions in different areas of chemistry. The discussion of the above problem is preceded by a review of data on tunneling phenomena in nuclear physics, atomic physics, solid-state physics, as well as on the tunneling effects in chemistry that go beyond the framework of the main subject of this monograph. This review is included to acquaint the reader with the role of tunneling phenomena in physics and chemistry as a whole, to show how diversified the kingdom of tunneling phenomena is, and to see more distinctly the similarities and the differences between electron tunneling in chemical reactions and other tunnel phenomena.




Atom Tunneling Phenomena in Physics, Chemistry and Biology


Book Description

Atom tunneling phenomena are a new paradigm in the science of materials. This book provides a wealth of interesting information about atom tunneling phenomena in physics, chemistry and biology. Topics include the theory of atom tunneling reactions, conclusive evidence and controlling factors for such reactions in solid hydrogen, tunneling dislocation motion, coherent tunneling diffusion, the production of interstellar molecules and semiconductors using tunneling reactions, the effect of atom tunneling on molecular structure and crystalline structure, the suppression of mutation and cancer by an atom tunneling reaction of vitamin C, and atom tunneling reactions of vitamin E and of enzymes. This book provides graduate students and nonspecialist readers with fascinating insights into the world of atom tunneling phenomena.




Tunneling


Book Description

Proceedings of the Nineteenth Jerusalem Symposium in Quantum Chemistry and Biochemistry, held in Jerusalem, Israel, May 5-8, 1986




Quantum Tunnelling in Enzyme-catalysed Reactions


Book Description

In recent years, there has been an explosion in knowledge and research associated with the field of enzyme catalysis and H-tunneling. Rich in its breath and depth, this introduction to modern theories and methods of study is suitable for experienced researchers those new to the subject. Edited by two leading experts, and bringing together the foremost practitioners in the field, this up-to-date account of a rapidly developing field sits at the interface between biology, chemistry and physics. It covers computational, kinetic and structural analysis of tunnelling and the synergy in combining these methods (with a major focus on H-tunneling reactions in enzyme systems). The book starts with a brief overview of proton and electron transfer history by Nobel Laureate, Rudolph A. Marcus. The reader is then guided through chapters covering almost every aspect of reactions in enzyme catalysis ranging from descriptions of the relevant quantum theory and quantum/classical theoretical methodology to the description of experimental results. The theoretical interpretation of these large systems includes both quantum mechanical and statistical mechanical computations, as well as simple more approximate models. Most of the chapters focus on enzymatic catalysis of hydride, proton and H" transfer, an example of the latter being proton coupled electron transfer. There is also a chapter on electron transfer in proteins. This is timely since the theoretical framework developed fifty years ago for treating electron transfers has now been adapted to H-transfers and electron transfers in proteins. Accessible in style, this book is suitable for a wide audience but will be particularly useful to advanced level undergraduates, postgraduates and early postdoctoral workers.







Quantum Tunneling in Complex Systems


Book Description

In the last two decades remarkable progress has been made in understanding and describing tunneling processes in complex systems in terms of classical trajectories. This book introduces recent concepts and achievements. There is particular emphasis on a dynamical formulation and relations to specific systems in mesoscopic, molecular, atomic and nuclear physics.




Dynamical Tunneling


Book Description

A prominent aspect of quantum theory, tunneling arises in a variety of contexts across several fields of study, including nuclear, atomic, molecular, and optical physics and has led to technologically relevant applications in mesoscopic science. Exploring mechanisms and consequences, Dynamical Tunneling: Theory and Experiment presents the work of i