Nuclear Magnetic Resonance Spectroscopy

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theoretically and not many have ventured into it. Perhaps this paper will win a few more converts. One of the most welcome chapters is that by R. Blinc on magnetic resonance in hydrogen-bonded ferroelectrics. Much remains unknown about ferroelectrics and to a greater or lesser degree each case seems somewhat special. However, it is clear that molecular motion and structural changes are generally involved in ferroelectric transitions, and this is precisely the kind of problem where the combination of continuous wave NMR and NQR, and spin-lattice relaxation measurements provides a tool of great power. Blinc’s extensive pioneering work in this field has shown what can be accomplished by concerted effort on well selected materials. We are certain to see much more of this research in the future. THOMAS A. SCOTT Dept. of Physics, University of Florida, Gainesville, Fla. 32601

Nuclear Magnetic Resonance Spectroscopy. By RUTH M. LYNDEN-BELL AND ROBIN K. HARRIS. Thomas Nelson and Sons, Ltd., London, 1969. 160 pp. 51 15’s,

$4.20 (paperback). Studies in Modern Chemistry Series. The most controversial aspect of this book is that it employs the Systeme International (SI) for the units of physico-chemical quantities. Thus, we have magnetic field strength expressed in teslas and reduced coupling constants in newton ampere squared per cubic meter. This system of units has much to commend it, but is virtually unknown to most American chemists. Even in Great Britain its use is by no means universal. In at least one prominent English university, SI units are taught in the department of physical chemistry and CGS units in the department of organic chemistry. If the SI system were universally employed, it would have the advantage that a completely consistent set of units would be learned and used throughout chemistry, physics, and engineering. It employs the meter, kilogram, second, and ampere (MKSA) as its basic units and all other quantities are coherent with these. Thus energy is expressed in joules (eliminating the familiar calorie) and distance in fractions of a meter (which eliminates the angstrom). SI treats electrical and magnetic units coherently instead of having separate electrostatic and electromagnetic units. But this means that the permittivity and permeability of free space have dimensions and often appear explicitly in SI equations. To older generations of NMR spectroscopists many equations will not be familiar, but to those teaching in universities which have switched to the SI system this book will prove extremely useful because the authors have been very careful and consistent in defining and explaining the notation used. The authors have succeeded admirably in their goal of writing a short monograph aimed at the lower graduate level which deals with the physico-chemical basis of NMR. It will appeal, as intended, to students of physical chemistry, chemical physics or theoretical chemistry. The first chapter covers the entire subject at the level an undergraduate should know it, including a rather poor discussion of notation for spin systems. The quantum mechanical basis for the analysis of NMR spectra is lucidly presented in the second chapter, but the practical matter of analysis of observed spectra by computer methods is mentioned only briefly. The origin of coupling constants and chemical shifts is covered in the third chapter. The relatively nonmathematical discussion of coupling constants is especially good. This includes a clear presentation of the Dirac vector model, electronic coupling of spins, the effect of hybridization, x-electrons and the stereochemistry of coupling, paying particular attention to the signs of the coupling constants. The last chapter on relaxation and double resonance deals with the Bloch equations, pulse experiments and the causes of relaxation and concludes with a brief description of spin tickling and decoupling. The last three chapters are intended to stand alone and can be read independently of each other. Unfortunately this leads to repetition especially of the figures. While it is probably inappropriate to give detailed references to the research literature in a book of this kind, the “Suggestions for further reading” are quite sparse. References to a few of the classic NMR papers at the end of each chapter would introduce the beginning student to the research

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literature. The problems at the end of each chapter are a particularly attractive aspect of this book. They serve well to review and extend the material in each chapter. Lynden-Bell and Harris have written a concise, readable book that fulfills a need in the NMR literature. KENNETH

L. WILLIAMSON

Dept. of’ Chemistry, Mount Holyoke College. South Hadley, Massachusetts 01075

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