Molecular Vib-rotors: The theory and interpretation of high resolution

The treatment in these basic areas is good, but not better than that in other currently available books. Some sections seem un- duly long, as though t...
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The treatment in these basic areas is good, but not better than that in other currently available books. Some sections seem unduly long, as though they were insufficiently condensed versions of lectures or class discussions. For instance, a t one point there is a detailed elementary explanation of how a bimetallic thermocouple functions. There is no attempt at exhaustive theoretical or mathematical treatment, but all the basic concepts are considered. There is a good glossary and a satisfactory index. The unique and valuable features of the book are as follows: I t indicates to the American reader the differences in European approaches, apparatus and procedures, though in terms of theory there does not seem to be much difference. Krell certainly gives much more information about German and European practice with regard to apparatus and procedures than has been published anywhere about the United States' equivalent. Thereis, thus, muchof interest in the way of laboratory-built or uommercially available equipment t~ndaccessories. There is a considerable discussion of laboratory continuous distillation, going quite beyond what is available in other books. There is an excellent hktarical introduction with good references and figurn. Items which raised questions or doubts in the reviewer's mind include the following: On page 86 the treatment of methods of evaluating vapor-liquid equilibrium data is inadequate in view of the otherwise extensive treatment of vapor-liquid equilibrium. On page94 the discussion does not show the basis for the graphical McCabeThiele procedure in terms of the underlying equations for material balance relations. On page 95 there is uncertainty as to whether the discussion applies to batch distillation or just to continuous. On page 264 the discussion of the effect of nonadiabaticity leads to confusing conclusions. On page 428 the data on singleturn helices are quite limited. On page 311 the discussion of steam distillation ignores the fact that component.? in general vary in the range of intermediate volatility between "volatile" and lLnouvolatile!' These items are listed, and some less importsnt ones could be added, partly to prove thst the reviewer and author are human, but more importantly to tantalize possible readers among distillation specialists. Examples of rewarding items for readers are: On page 6 the mention of Cleopetrs.; on page 45 and elsewhere the organization of the discussion into sections on analytical distillation, preparative distillation, production distillation, and a distillation for comparison with a large-scale operation; on page 65 and nearby p a g e the discussion of vapor pressure and vapor-liquid equilibria; on page 98 the mention of Billet's work; on page 218 the combination of batch and continuous distillation; on page 250 the use of the term "unfractiouated distillation"; on pages 281-2 the finding of leaks with a stethoscope, with a fluorescent dip, or with a thermistor device; and on page 293 the separation of substances of identical vapor pressures by molecular distillation. The printing and format are very good. A very helpful feature is the footnote on each right page telling where references for that section may be found.

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Journal o f Chemical Educafion

The reviewer was surprised a t the number of instances when the reference given to support discussion of a significant idea or concept or technique was not the one familiar to United States readers, but was selected from the German or often the Eastern European literature. Possibly an important reason for owning the book is to have it serve as a convenient entry to this redm of the technical litersture. The Krell hook should serve as a stimulating adjunct to other distillation literature summaries in every distillation course and laboratory, and should be present in every library having B clientele interested in distillation. ARTHURROSE Pennsylvania State University Uniaersity Park Chemical Infrared Spectroscopy. Volume 1, Techniques

W . J . Potts, Jr., Dow Chemical Go., Midlands, Michigan. John Wiley and Sons, Ine., New York, 1963. xvi 322 pp. Figs. and tables. 15.5 X 23.5 em. $8.50.

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The stated purpose of this volume is t o collect in s. convenient place information of value to the practicing chemical infrared spectroscopist. This objeotive has been achieved with clarity and with a degree of background development not found in most other works. A great deal of the material presented is familiar to most spectroscopists. The organization and the treatment of the subject matter, however, clearly present to the interested chemist a weelth of infommtion concerning infrared spectroscopy and its practical utilization in solving chemical problems. The title of this work is misleading since the book deals with many aspects of infrared spectroscopy which cannot be categorized by the term, "Techniques." The author has included an introduction to the theory of infrared spectroscopy (Chapter 2), a discussion of the infrared spectrophot,ometer (Chapter 3) itnda thorough, interrsting tmatment of ,fpectrophotonleter performance and operation (Chapter 4). The discussion in Chapters 3 and 4 presents principles of speetrophatometer construction, performance and operation in a concise, refreshing manner, rather than the ritualistic comparisisun of various commercial instruments so frequently encountered in other books treating the same material. These chapters will be of interest to all chemists using infrared epectrompy in their work. The last cbptepter (Chapter 8) outlines the theory of infrared spectre. of polyatomic moleoules. The reader is led through an abbreviated diseussion of molecular vibrations, symmetry properties and rotationvibration bends in expert fashion. This chapter is by far the outstanding contribution of the volume; it impruts a familiarity with the meaning of the results of the theory rather than overwhelming the reader with a detailed mathematictl treatment. The quditative appreciation for the theory of infrared spectroscopy which the author achieves here will be of interest and value to a large number of chemists. Perhaps the weakest portion of the book

is the treatment of specifictechniques used in preparing samples and in obtaining a suitable infrared spectrum of a material. These techniques are discussed in two chapters (5 and 7) which are far too brief. The sections on the preparation and use of cells are incomplete and, in part, outdated. Many excellent techniques fur window preparation are completely omitted. In addition, the sections on microssmpling (e.g., the use of cavity cells) and on attenuated total reflection are given only a hrief passing treatment, leaving the impression thst they are rather special techniques of minor importance. Throughout the discussion of techniques, no detailed delineation of the effect of sample state and method of preparation on the recorded spectrum could be found. This is unfortunate, since one does not gain ctn sppreciation of the necessary restrictions, dependent on these parameters, which must be applied to the interpretation of spectral data. Despite these deficiencies, both academic and industrial chemists will find this volume of interest. The writing is clear, to the point and the book is certainly a valuable addition t o the literature in the field of spectroscopy. For those seeking introductory information regsrding infrared spectroscopy and its applications, this volume, together with the projected second volume, should provide any neophyte in the area a storehouse of food for thought. ROBERTT. CONLET S e t a Hall University South Omnge, New Jersell Molecular Vib-Rotors: The Theory and Inlerpretation of High Resolution Infrared Spedra

Harry C. Allen, JT., Nstional Bureau of Standards, Washington, D. C . , and P a d C. Cross, Mellon Institute, Pittsburgh, Pennsylvania. John Wiley and Sons, Inc., New York, 1963. vii 324 pp. Figs. and tables. 18.5 X 26 cm. $13.50.

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The study of the line structure of molecular vibration-rotation bands dates from the measurements of 1910 to 1914 by Eva van Bahr. Over the intervening years many of our most revealing insights into the exact shapes and sizes of molecules and the interactions between their parts have come from these infrared investigationians. Unfortunately, the specialized techniques of the analyais of vibration-rotation spectra have been scstt,ered among a multitude of papers in the literature, often with quite different choices of notation. The monograph by Dm. M e n and Cross represents the fimt major effort to bring this material together in a readily available form, with consistent notation throughout. Starting with the separation of the Hamiltonian, the problem of the rigid rotor is treated, with and without the presence of symmetry, including various levels of approximation to the energy states of an asymmetric rotor. Building on the rigorous treatment of the separation problem, the cross terms that appear (Continued a page A5301

are treated as perturbstions of the rigid rotor states and the intensities of the possible transitions are examined. Linear molecules, symmetric rotors, and asymmetric rotors each receive a chapter, in which the methods presented earlier are discussed in greater detail, with applications to individual molecules. Nearly a third of the book is devoted t o appendixes which provide some additional proofs and many of the tabulated values that are useful in the application of the theory. Because of the limitations of space, the treatment is nenssarily sketchy, though rigorous. It is made clear by statements in the text and by the choices of starting points or amieaions of details that the reader is expected to rely heavily upon existing literature for filling in and extending the treatments given. Examples of subjects that are largely untouched include spherics1 rotors, contours of unresolved or partially reaolved bands, broadening and shifts caused by molecular collisianq experimental sspecta, and det& or refinements of primary interest to the microwave region. The bibliography is selective (126 references). The accuracy of the process of reduction to the printed page is generally high; the error of sign in the original definition of the Coriolis force (p. 48) might cause some temporary confusion but otherwise the errors noted were quite trivial. Clearly thia is a work that will be an important reference for those who have only occasional need for the methods or results of rotation-vibration analyses and will be an indispensable handbook for those who undertake such analyses.

Alternating Current Polarography and Tenrammegry

B. B~eyerand H. H. Bauer, both of the University of Sydney, Austrdia. Chemical Analysis Series, Volume 13. Interscience Publi~hers(a division of John Wiley and Sons, Inc.), New York, 1963. xix 288 pp. Figs. and tables. 15.5 X 23.5 cm. $12.00.

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"Alternating Current Polarography and Tensammetry" repments the fimt comprehensive discussion and review of the most widely applied electrochemical relaxation technique. The authors are eminently qualified, having contributed more puhlished work to this field than any other group. Their pioneering efforts have led to the present rapidly expanding popularity of the technique. The text consists of five chapters. Chapter 1 is a brief, but well-presented description of the historical development of ac polarography and of the various important facets of the ao polarographic process. Chapter 2 is an introduction to the quantitative theory of ac polsrography. Instrumentation is discussed in Chapter 3. Chapter 4, entitled Analytical Applications, is, in fact, primarily a comprehenaive review of experimental results obtained with chemical qwtems subjected to ac polarographic investigation with emphssis on andysis.

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Journal of Chemical Fducofion

The last chapter deals with elucidation of electrode processes on the basis of qualitative examination of ac polarographic behavior. This text is directed p r i m r i b to the reader with little or no knowledge of ao polarography. The authors' intent, as stated in the Preface, is ',to acquaint the reader with the essentials of the new technique and to show how it can be usefully applied both in analytical work and in the study of electrochemical processes." This reviewer feels that the text will serve admirably its intended purpose. The new worker in the field who US= this hook should acquire sufficient knowledge of the technique to enable intelligent perusal of the more advanced literature. To the already active, wellread worker in the field, this text most likely will represent little more than an extensive review of the subject and a most useful reference work. Aa a review article, the book is by far the best mailable. It suffers somewhat by the fact that it includes little work published since 1960 and it contains some omissions of significantwork prior to 1960. The book must be judged good to excellent regarding its merits as an introduct,ory work. Well-treated are diseusaions of the origin and importance of the various current components arising in ae polarography, the important considerations in instrument design, electronic methods of enhancing sensitivity for analytical work, the use of qualitative data in electrode mechanism elucidation and the scope of puhlished work on ac polarography. Discussions of these topics are presented in a qualitative fashion with a minimum of mathematical relations. The weakest section is the treatr ment of the quantitative theory, Chapter 2. While the derivation and discussion of the theory for the ac polarographic wave with an electrode process kinetically influenced by charge transfer and diffusion serves to shorr the reader how the theory is approached, the anthorn' desire to keep the theoretical treatment simple leads to oversimplification in some areas. The authors do not consider how a kinetically controlled dc process influences the ac wave. While this omission certainly is justifiable on the bsais that the authors desire to maintain isimplicity, the statement tbat ' k c polarographic waves are generally observed only when the dc process is reversible" is incorrect and misleading. The careful reader will find numerous charge transfer rate conatants cited in Chapter 4 of this book which were determined by ac methods and were sufficiently small (kh < lo-' cm sec-1) that the de process could not be strictly reversible. Cases in which ac waves may be observed under conditions in which chemical reaction or adsorption processes kinetically influence the do wave aIso are encountered frequently. Chapter 2 would have benefited by the omission of the extended treatment of the fundamental harmonic and the treatment of the second harmonic. While the authors took care to indicate that the mathematical approaches were "simplified," this reviewer believes the word ~rmcorrect" to be more appropria,te. The uninitiated reader can only be

confused and led to incorrect qualitative conclusions from these treatmenta. A need for a text on 80 p018rography existed. Breyer and Bauer's contribut,ion adequately satisfies that need. The book will serve well as a reference text and as an introduction to the field. Issue may be taken with some specific points, but this does not seriously detract from the value of the work.

E.SMITH DONALD Northwestern Uniwrsiry Euanston, Illinois The Physics of Experimental Method

H . 3. J . Bmddick, University of Manohester, England. 2nd ed. Reinhold PublishineCorn. New York. 1963. xxiii 480 i p . 'Figs. and tables. 14.5 X 22.5 cm. $12,

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This book is intended to call the attention of the reader to some of the principles of experimentation and to some of the available techniques. There is a definite emphasis on physical principles throughout and a corresponding paucity of the details of particular experimental techniques. The research scientist might therefore refer to this book in order to gain a preliminary understanding of an unfamiliar experimental method. The author begins with afairly extensive chapter on errors and the treatment of experimental data. Chapters on mechanical design, construction materials, and a short chapter on vacuum techniques follow. The remainder of the book deals with electrical measurements, electronics (including a brief description of tramistor applications), optics and photography, photoelectric detectors, and the effect of noise on measurements. The last chapter surveys eome experimental techniques of nuclear physics. Many of the chapters have appendixes containing details of recent developments or other information more-or-less associated with the text. A narticuladv valuable feature found throughout is the generous number of references to other books or to the original literature. The first edition of this book was published by Chapman and Hall in England in 1954, and Reinhold is introducine the second edition to the American sciengfic community. It should not be difficult for the American research scientist to obtain construction materials mentioned in this book, because, wherever possible, the author has identified the American analogue to materials of the British trade. This reviewer has found tbat certain sections of the chapter on vacuum technique are somewhat outdated in the light of recent developments. The same may be true of other chapters, and in this connection less than 5y0 of the 300 references in the bibliography are dated 1960 or later. The majority of references is taken fromthe literature prior to 1950. Also, in the light of a great deal of current physical research, the omission of a dwcussion of cryogenic experimental techniques and principles must be regarded as a serious deficiency.

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