Organic Functional Group Analysis. Theory and Development (Schenk

Theory is included. Thelinear variation .... tonian, the theorem should havebeen in- troduced there, rather ... George H. Schenk, Wayne State Uni- ver...
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in comparison with a "time aversge," would be essentisl a t this point. From the moment we have left the "postulates" behind us, the level of presentation abruptly changes to a much more elementary one and the various topics (particle in a box, harmonic oscillator, rigid rotator, etc.) follow in more or less routine fashion. Unfortunately there are far too many disturbing features. These cover the entire spectrum from obvious misprints and misspellings, through occasional confusion in nomenclature and notation, all the way up to statements which are somewhat misleading to plainly incorrect. Let us cite some examples, all of which struck us a t a first reading. The various items are. given roughly in the order in which they appear. Comment is only given where deemed necessary, and italics are the reviewer's throughout. "The operators for the components of angular momentum do not commute because they correspond to the same observable" (p. 5). "Th'hdr < m at all voints" (D. .. 8). . (The continuity requirement on $ is not mentioned.) As part of section 1.5, Approximate Methods, 8 subsection on Variation Theory is included. The linear variation function is introduced as " 6 = Z cixi

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in which the xi fmm a cwnplele set" (p. 29). Now there is nothing approximate in the variational procedure as such, and if the xi did indeed form a complete set, minimization of the energy should give us the exact ground state wave function. The approximation as such does not enter the treatment until we truncate the set of xi and, in practice, this we are forced to do. On the same general subject, on p. 59 a configuration interaction wrtve function is written down for the first time. In comparison with the single-configuration description, it is stated ". . provided that a sufieimt number of determinants are chosen, the energy will be lower." Of course even the addition of a single interacting configuration function has to lower the energy. Just below this the author . of the concludes "One advantage . is configuration interaction method that the number of t e r m in the wave function can be extended a t will." To be honest, we should tell the student a t the same time that because this extension is limited by the capacity of our computer, and such down-to-earth factors as the amount of computer time available to us, the serious disadvantage of this method is just how to select all of the most important terms and still remain within those limits. To illustrate the notion of a Slater determinant, the (10 X 10) one for the olosed-shell ground configuration of the fluorine ion is written out in full (p. 47). (A minor point: When everything is writtenout explicitly with special reference to F-, why is the normalization constant not written as l/.\/El! rather than as 1 ? Quite apart from the fact that this seems a waste of space (the corresponding determinant for Be would be a lot easier to look at, and bring out all the same essential features) someone forgot to attach subscripts z, y, and z to the 2p atomic orbitals. Thus, as printed, the

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determinant is eero on amount of no less than three pairs of equal rows! The usual ladder operators are introduced here, with the statement: "These operators are often known either as step-down and step-up operators or in specific contexts as annihilation and creation operators" (p. 48). Now the farmer designation should he clear from the presentation a t hand. The more inquisitive student, however, will certainly ask what is "created" and what is "annihilated" here. No second quantization formalism is introduced anywhere in the baok. The sentence: "When m has its lowest possible vahlne, M, - i M , annihilates the rotating particle . . ." is of no help whatever. On page 62, with reference to the BornOppenheimer approximation the author states, "Provided that there are no inleractions between the electrons and the nuclei, a wave function can be assumed, . . .". The valence bond wave function for Hz is written in the form $ = ct ILCOV cz fij, with the conventional designation for "covalent" and "ionic" terms (p. 74). I t is stated that: "The small value of ( . , . obtained by the variational procedure . . .)justifies the Heitler-Lmulon assumption for the neglect of ionic tenns (at least in the case of the hydrogen moleode." The crux of the matter is that fie., and +bia,, are defined in such a wsy that at the equilibrium distance in Hs .fficoy d r = .95. We are attempting to represent the mutually exclusive concepts of "ionic" and "covalent" by very similar wave functions, even if this is not apparent a t first sight. Thus the fact that $ion appears with a small coefficient could have been predicted, and tells us absolutely nothing ahout how good an approximation fi,,, is to the true groundstate wave function. Koopmans' Theorem is written as Koopman's Theorem (the scientist involved is T. Koopmans) (p. 125). The erroi also appears in the index. Since the energy of many-electron atoms was disc~wed in section 2.9, with explicit electron interaction t e r m in the hamiltonian, the theorem should have been introduced there, rather than in section 5.7 within the framework of Hiickel type theories, where it is far less revealing. All this does not mean that this hook is without any assets. There are some very readable sections and the author has managed to compress a lot of material into relatively few pages. We do not wish to enter the fruitless discussion as to whet could hsve been omitted and what might have been included in a course of this type. We all have our own personal preferences and Dr. Pescook is entitled to his. But on the whole there is very little here that has not already been written down over and over again. There is undoubtedly a need for more hooks in the general area. of quantum chemistry. Personally I would like to see a text which presents some of the more modern advanced mathematical techniques (density matrix theory, the use of Green functions, applicatious of the second quantization formalism) in readable form. I keep an men mind with resnect to new and trulv original presentations of what is otherwise familiar material. But I cannot under-

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stand why the publisher of Eyring, Walter, IGmball and Murrell, Kettle, Tedder, just to mention two very different representatives of a long list of excellent hooks in the same general area, saw fit to print another short introductory text along largely conventional lines. And we have to challenge the publisher's claim (hack cover) that "The degree of rigour achieved should satisfy the most exacting student and lecturer.. . . ."

J. DE HEER Unive~sityof Colorado Boulder. Colorado 8050Z

Organic Functional Group Analyrir. Theory and Development

George H . Schenk, Wayne State University, Detroit, Michigan. Pergamon Press, Inc., New Yark, 1968. x 297 pp. Figs. and tables. 13 X 19.5 cm. Psperhound, $4.50.

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The emphasis in Professor Sehenk's baok is on the subtitle, "Theory and Development." I t would perhaps have been better if the title had emphasized this through rephrasing so that a clearer differentiation could be made between this hook and the similarly entitled volumes of Siggia ("Quantitative Organic Analysis via. Functional Groups," see T H ~JOURNAL, 40, 470 (1963)) and Critchfield ("Organic Functional Group ~ 407 Analysis," see THIS J O U R N A41, (1964). Professor Schenk's hook is not a substitute for those works; rather its apparent purpose is to allow the reader to develop an appreciation for the chemistry emphasized in functional group sndysis and lead him through the development of a, number of methods. To this end the book is divided into two parts: the first part consists of seven chapters which me historical, descriptive, and critical of the development of s. method for a. functional group; the remaining 24 chapters in Part I1 consist of the original papers which are used as the basis of Part I. The student (for whom the hook jacket states the book is designed) e m thereby read both the original papers and follow a critical evaluation of a. body of work. The seven subjects chosen are: oxim* tion determination of carhonyls; determination of enolic groups; base catalyzed acylation of hydroxy and amino groups; acid catalyzed acylation of alcohols and alkoxysilrtnes; the determination of epoxide groups; Diels-Alder addition to 1,3-dienes; determination of electron rich compounds by formation of donor-acceptor complexes. The subjects as stated by Professor Schenk are all in line with his research interests but present enough variety to give a wide view of functional group analyses. It also insures that the author is thoroughly familiar with his subject. Although most of the discussions center

Volume 46, Number 10, Odober 1969

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about chemical resetion as the means of analysis, references are made to instrumental methods, especially nmr. I n the case of primary and secondary alcohol i t is shown how ac~lation followed by nmr analysis was used to determine the components of a mixtwe. This was not possible by nmr alone. The advocacy of a mix of chemical and instrumental techniques may induce the reader to do more thinking in this area. Two minor errors were noted, an unbalenced q u a t i o n on page 45, and an incomplete sentence on page 75. The book should make thoughtful and informative reading for both students and practicing chemists. C. A. STREULI Ammican Cyanemid Company Stamford, Connecticut

Organometallic Compounds of the Group IV Elements. Volume 1, The Bond to Carbon Edited by Alan G. MacDianid, University of Pennsylvania, Philadelphia. Marcel Dekker, Inc., New York, 1968. Part 1, r v 603 pp.; Part 2, xiii 261 pp. Tables. 16 X 23.5 em.

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$17.75.

This new series promises to be a valuable addition to the ever-increasing number of books of the "advances" type. The editor structures the series in the introduotion by stating "Each volume will be devoted to a discussion of a group IV element-X bond, where X is s. specific element or group of elements." The initial volume, which deals with the group IV-carbon bond, has a n underlying theme as a result of this structuring. The reader can depend upon the scope of the material to be found in each section. Further, the chapters on the individual elements are organized in a consistent fashion, first presenting information on how the group IV-carbon bond is formed and then discussing the reactions of this bond. Limiting the scope of each volume has some small disadvantages. A certain amount of repetition is to be expected. For example, Volume 2 will treat the group IV-halogen band hut the reaction of this bond is extensively treated in the initial volume as a prime method for the formation of the group IV-carbon bond. Also, reaction types which show some addition to generality (e.g., EM-H EM-X) are not alkenes, and R-Mg-X sufficiently compared. However, on the whole, i t is felt that more is gained than lost by this strict organizetion. The first chapter is s general view of the important physical properties of the erorm IV elements and their com~ounds. It dcd. priucipdly with atomic ~ T I I ~ ~ I I C and tllr proprrriei of s r d l ~qmurnt.rnllic n d c c d e ~ . T h v curreut evidwcc for the existence and extent of (p d) r bonding is critically examined. Ebsworth's comments an what is well understood (or, mare properly, what isn't!) about these supposedly simple properties is a t times refreshing and often not too gentle. For example, in discussing the donor proper-

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Journd o f Chemical Education.

ties of some organometallic compounds based on heats of formation, he states "The assumption is of course unjustified; .. .but as usual the assumption serves as a basis of a. simple-minded discussion of the problem.'' The chapter by Eaborn is devoted to an extensive review of the current literature through 1967. Of the more than 2500 references, more than 607! are from 1960 or later. This accurately reflects the explosive growth of research in the organosilicon field. The approach is from s preparative point of view, with mechsr nistic information interspersed when availdde. The extensive section on the addition of silicon hydrides to alkenes is particularly noteworthy. This area. has developed very rapidly over the last fifteen years, making the need for such a review acute. The last three chapters on germanium, tin, and lead present a contrast on the basis of size alone. Combined, they are only about one half as large as the chapter or organosilicon compounds. This perhaps reflects that research in these areas lags far behind. Overall, the style of the several contributors was found to be consistent. This is quite often not true in compilations of this type. I t is felt that the initial volume of this series will be useful as reference material for graduate courses and will serve as an invaluable aid to those interested in research in this area. DANIELH. O'BRIEN Tezas A & M University College Station, Tezas

Plasma Spectroscopy Geoffrey 7. Maw, J. J. Thomson Physical Laboratory, Reading, England. American Elsevier Publishing Co., New 316 pp. Figs. and York, 1968. ix tables. 15 X 23 em. $21.50.

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I n the author's words this hook first "aims to provide a text suitable for use in the undergraduate course which gives an insight to those aspects of spectroscopy which are relevant in the analysis of luminous sources currently classed as plasmas!' Secondly, "it is hoped that it will also be of use to graduate students and to research workers requiring an introduction to those aspects of plasma diagnostics which need spectroscopic techniques!' I n this review the book is judged inview of these objectives. The book is obviously written primarily for physics students. However chemistry students are expected to benefit from i t as far as understanding of the principles of atomic spectroscopy. The book consists of eleven chapters including the introduction in which the above concerns are expressed. After a brief account of plasma I fundamentals in chapter two the interaction of matter with electromttgnetic radisi tion is introduced in chapter three with emphasis on the transition probabilities. The next four chapters cover atomic spectra and electronic spectra of diatomic molecules. The treatment, b a d on the wave equation and quantum mechanics, is rather brief. Helpful detaila such as energy levels and transition and correla-

tion diagrams are either few or omitted. Although an introductory course in qumturn mechanics is not essential for an adequate understanding of the subject, the haokeround in ouantum mechanics pr..vidcd i t . the tbook i i rwr stllticwtt ljy ltscli 31.4l h r h tenrhernrd r t m l u l have to seek other texts on quantum mechanics to fill the gap. With these difficiencies standard books on atomic spectroscopy and spectra of diatomic molecules would be a better choice for a course to fulfill the first objective. Bound-free and freefree transitions, which are important processes in plasma sources have not been given enough attention in standard spectroscopy texts. The author is commended far assigning each a separate chapter. In spite of the importance of processes associated with these transitions in plasma sources and the detailed treatment they deserve in a. specialized hook on plasma spectroscopy the treatment here is brief and in the fashion of a. review article. The last two chapters deal with the shapes and widths of spectral lines and with plasma diagnostics such as temperature and density measurements. I t is in these two chapters where a background in atomic spectroscopy and electronic spectra of diatomic molecules is applied towards plasma diagnostics. The contents of the last five chapters serve the second abjective. However the pure theoretical treatment leaves the experimentalist unsatw fied. Practical examples and illustrations backed by the instrumental aspects of spectroscopic techniques are omitted. I n generd the book is suitable as a text for one semester specialised course but requires an introductory course in quantum mechanics as a prerequisite. The lack of exercises and problems a t the end of each chapter could be an undesirable feature of this book as a text. In spite of the above limitations, the author is successful in his wide coverage of a vast topic in a brief book. The price of 521.50 for a book of 316 pages is unreasonable. ~

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ADLIS. KANA'AN Western Michigan Uniwrsity Kalamazoo, Michigan

Chimie Organique Donald J . Cram, University of Calfornia, Los Angeles, and George S. Hammond, California Institute of Teehnology, Pasadena. Translated by Philibert I'ficuyer, Universit6 Laval, Qu6bec. 2nd ed. Gauthier-Villars, Paris, 1968. (Available from Les Presses de 1'Uni1152 pp. versit6 Laval, Quebec.) vi Figs. and tables. 16 X 25 cm. $17.50.

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Here is Cram and Hammond en franc&. The familiarity of this classic (See THIS JOURNAL, 40, 668 [19631) and now the ready availability should combine to make investing in a copy an excellent way to learn scientifio French. Though manstrous and weakly bound, the book maintains the original beauty of composition and,c.ontrasting color. WFK

(Continued on page A760)