Books

Basic Principles of Proton NMR

An Introduction to Proton Nuclear Magnetic Resonance Spectroscopy. Addison Ault and Gerald O. Dudek. viii + 141 pages. Paperbound. Holden-Day, Inc., 500 Sansome St., San Francisco, Calif. 94111. 1976. $4.95 Reviewed by Jerry P. Heeschen, The Dow Chemical Co., Analytical Labo-ratories-574, Midland, Mich. 48640

Here is a lucid introductory text de­signed to acquaint the student with the simplest basic principles of ob­taining and interpreting proton NMR spectra. Written as a useful adjunct to a first-year course in organic chemis­try, it also could serve as a self-teach­ing device for persons who use NMR as an incidental part of their work or for instrument operators not engaged in interpretation. A knowledgeable re­source person should be available to answer inevitable questions, particu­larly for answers to the problems at the ends of chapters.

The book is well organized. Each chapter develops in complexity from start to end, and the subject matter proceeds likewise from one chapter to the next. The problems following each chapter deal with basic concepts and are instructive, but answers are not given. There are many illustrations. Most spectra appear to be at 60 MHz, although this is not stated.

The presentation is entirely de­scriptive. The only "precise" relation­ships given are first-order splitting patterns, chemical shift additivities for methylenes, and a formula for de­termination of molecular weight by use of an internal reference. Nonfirst-order patterns such as AB, AB2, AB3, A2B3, and ABC are discussed and il­lustrated, but not even the simple ex­pressions for the line positions and in­tensities of an AB system are offered. There are charts of chemical shifts and a tabulation of proton-proton coupling constants.

Four chapters are noteworthy. One examines magnetic equivalence well, and this is a key aspect of the utility of NMR. The chapter "Interpretation of Proton NMR Spectra in Terms of Mo­lecular Structure" discusses several known structures before venturing into the unknown. Two chapters on sample preparation and scanning spectra are useful for the novice. In addition to these chapters, an Epilo­

gue alludes briefly to spin decoupling, computer techniques, quantitative analysis, other nuclei, and shift re­agents.

Only one editorial error was noted— the spectra for Figures 4-9 and 4-11 are interchanged. The informal writ­ing style reads well, although there are occasional grammatical errors.

This reviewer finds the remarkable dearth of simple mathematical rela­tionships regrettable, because the math can be instructive and should not be incomprehensible to any un­dergraduate science student. One case in point is the AB quartet mentioned above. In another instance, the origin and detection of spinning sidebands are discussed, but it is not stated that their separation from the central line is equal to the spinning rate.

There are few unfortunate instances of inaccurate or over-simplified state­ments on complex topics. These gen­erally are not critical to the argument at hand, but could be confusing for the serious student. In one place it is stat­ed vaguely that for solids "intermolec-ular forces produce broad lines". Else­where, the ringing after passage through a sharp line is described as a pen oscillation rather than as a re­sponse of the nuclei which have just been irradiated.

It is surprising that there is no bibli­ography referring the serious student to standard textbooks or to collections of spectra. Only two references are given—one to the two Varian volumes of spectra and the other to an article on magnetic equivalence.

In summary, this is a well-written descriptive introduction to proton NMR, suitable for first-year organic chemistry students and incidental users of the method. It is not suitable as a quantitative introduction to the method or as a general reference book.

Radio and Microwave Spectroscopy. David J. E. Ingram. 167 pages. Halsted Press, 605 Third Ave., New York, N.Y. 10016. 1976. $12.95 Reviewed by W. H. Flygare, School of Chemical Sciences, University of Illi­nois at Urbana-Champaign, Urbana, III. 61801

This book attempts to summarize, in a very qualitative way, spectroscop­ic applications of the radio and micro-

ANALYTICAL CHEMISTRY,

wave regions of the electromagnetic spectrum. This is roughly in the 50-MHz region for NMR and the 20-GHz region for ESR and microwave spec­troscopy. The book is aimed at the college undergraduate in about his second year. The strong points include good summaries of the beginnings and initial developments of the fields of ESR, NMR, and microwave spectros­copy including good illustrations of the original apparatus in each case. The author has a fine grasp of the subject, and his attempt to give a qualitative picture of the physics in­volved, without any help from the basic theory, comes off fairly well. The author has also been astute in his dis­cussion of the pure and applied as­pects of the fields of radio and micro­wave spectroscopy.

There are also some weak points. In spite of mentioning several of the orig­inal workers' names, no references are given anywhere. I certainly think that the average undergraduate would ap­preciate a few references to follow-up areas that interest him. There are only two tables of data in the entire book. More data pointing toward the infor­mation on molecules and about the structure of molecules would have been very useful in illustrating the principles (at least to chemists).

It is hard to fit this book into a standard curriculum in the U.S. as a unit course as suggested by the au-

VOL 49, NO. 2, FEBRUARY 1977 · 235 A

Books

thor. The book is too qualitative for a unit course in a chemistry curriculum. I t would provide good outside reading, however, for a s tudent in his second or third year of the chemistry curricu­lum. Most courses in physical chemis­try, taken in the second or third year, have a relatively quanti tat ive but short presentation of the principles of ESR, NMR, and microwave spectros­copy. This book would provide good outside reading for the origins and ini­

tial developments of these fields as well as providing the reader with a summary of applications which, unfor­tunately, are weak on the side of mole­cules and molecular structure.

Environmental Pollutants: Selected Analytical Methods. Wilfred Gallay et al. 277 pages. Ann Arbor Science Pub­lishers Inc., P.O. Box 1425, Ann Arbor, Mich. 48106. 1975. $22.50 Reviewed by Rudolph H. Stehl, Ana­

lytical Laboratory, Dow Chemical U.S.A., Midland, Mich. 48640

This book, a compilation of meth­ods by a subcommittee of the Interna­tional Council of Scientific Unions, contains 45 specific methods for ele­ments or compounds. It includes methods for airborne lead, cadmium, zinc, copper, nickel, manganese, co­balt, beryllium, vanadium, chromium, selenium, arsenic, mercury, fluoride, nitrate, ozone, sulfur- and nitrogen-oxides, and benzo-a-pyrene. There are also methods for some of the above species as well as phosphate, pesti­cides, and PCB's in water and/or bio­logical fluids.

Each of the methods is presented in the same format, which greatly facili­tates the comparison of sample collec­tion, t reatment , and measurement procedures. In addition to accepted techniques and procedures using atomic absorption spectroscopy for metals, a number of methods of esti­mation using the Weisz ring-oven technique are presented. Gas chroma­tographic methods are presented for pesticides and PCB's, while fluores­cence is recommended for the mea­surement of benzo-a-pyrene.

In general, the methods presented are accompanied by quantitative ex­pressions of the overall and the instru­mental precision and the observed limits of detection for the specified types of samples.

Some discussion is devoted, in each of the methods, to sample collection, sample t reatment , instrument operat­ing conditions, and calculation and ex­pression of results. In addition, notes on the procedure are given with com­ments on critical or troublesome parts of the procedure. Each method is ac­companied by a limited number of ref­erences to the original literature.

The only criticism which might be made of this collection of methods is tha t too little attention is paid to the sampling procedure itself. However, the complexity of tha t topic and re­cent other references to methodology on sampling ("Residue Reviews", Vol­ume 55) make the editor's cautionary comments on sampling very appropri­ate. With the increasing instrumental sensitivity available, the importance of representative and accurate sam­pling procedures must be appreciated by the analyst.

This book will serve as a valuable addition to the library of analytical as well as environmental scientists to provide a collection of documented, validated methods for some potential­ly hazardous compounds and ele­ments.

NEW WILKS IR ANALYZER:

Compresses α full clay's worth of quantitative analysis into a few minutes!

The Wilks Model 80 combines a high performance single beam infrared spectrometer with a programmable microcomputer. The result: a completely new quantitative analysis system with unmatched speed and versatility. The Model 80 Analyzer accepts solid, liquid or gaseous samples directly — no need to vaporize or dissolve them or separate them into their individual components. Simply fill a cell, push a button and, in less than a minute, the analysis is printed out in percent, parts per million or whatever scale is required.

The Model 80 handles mixtures with up to 11 components, is compatible with all transmission or reflection sampling systems, is rugged and portable, requir­ing no services other than power.

The Model 80 Infrared Analyzer will completely change your concept of quan­titative analysis. Call or write for a demonstration.

P.O. Box 449, So. Norwalk, CT. 06856 (203) 853-1616, TWX 7104683206. UK Office: Wilks Scientific, Ltd., 64 Burners Lane, Kiln Farm Employment Area, Milton Keynes, Bucks, England.

See this instrument on display at the Pittsburgh Conference, Booths 937 & 939.

CIRCLE 233 ON READER SERVICE CARD

236 A · ANALYTICAL CHEMISTRY, VOL. 49, NO. 2, FEBRUARY 1977