Chemical applications of group theory (Cotton, F. Albert)

For these reasons, ,&ton and Turner me generdly conservative about the present poasihilities of the use of chemistry in taxonomy (although some striki...
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For these reasons, ,&ton and Turner me generdly conservative about the

present poasihilities of the use of chemistry in taxonomy (although some striking successes are eitcd). They do, however, hold out exciting hopes for the future, when the difficulties will have been overcome, and the classification of plants placed on a logical genetic basis, rather than on the rather unsatisfactory marphological one on which it now rests. This book reveals careful thought on the part of the authors; it is extremely well written, and, although not many chemists are specifically interested in t h i ~field, it is quite fascinating to the biochemist who ia interested in seeing the uses to which ilia discipline may be put. I t is also beautifully documented, the references ranging from antiquity right up to 1963. The only adverse criticism is that the figures and tables are not adequately explained. "Biochemical Systematics'' is highly recommended for browsing by the average chemist, and far study by those in the field. PETEROEBPER Hahnemann Medical College Philadelphia. Pennsylvania

Lectures in Materids Science (The Cornell Materials Science Center Lecture Series)

Edited by P a d Leurgms. W. A. Benjamin, Ind., New York, 1963. viii 109 pp. Figs. and tables. 16 X 23.5 em. Clothbound, $7. Paperbound, 8.95.

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This book consists of four lectures given at the Cornell Materials Science Center, by four distinguished scientists: F. Bitter, N. Bloembergen, P. J. W. Debye, and P. J. Flory. The Introduction to the volume, which was also the introduction to the lecture series, was given by S. S. Atwood, who pointed out that these talks were meant to cover special topics in the field of materials science and to broaden the perspective of first-year graduate students. Unfortunately, the chosen topics, however expertly presented as individual lectures, constitute only isolated aspects of the generd field of materials science. Moreover, the level of sophistication and the breadth of coverage vary so widely among the lectures that any given reader is likely to 6nd only fragmentary value in the contents. This book therefore serves mainly as an archive for the leotures, and not ass, broadly useful source of information. In the first lecture. P. J. W. Dehve dis-

composed of small molecules snd those containing polymers, and discusses what the phenomenon tells about molecular dimensions. The subject is important in polymer science, and hears the influence of Professor Debye both as a pioneer and as a current worker. The treatment is fairly advanced, in terms of the experience of 6mt-year graduate students, but the story is expertly and delightfully told.

In the second lecture, P. J. Flory discusses Macromoleculesin the Solid State. He deals mainly with the configurations of linear chains, which largely determine the spatial dimensions of macromolecules both in solution and in the condensed state. Professor Flory is a leading worker in the statistical thermodynamics of macramolecules, and has expertly surveyed much of the field in this lecture. The paper requires sophistication in mathematics and statistical mechanics well beyond the ability of most first-year graduate stndents. The content is condensed and modern. The paper is most likely to he useful to a. polymer soientist who knows something about problems involving chain configuration and who wishes an authoritative renew. In the third lecture, N. Bloembergen discusses Magnetic Resonance and Its Applications. This paper touches hroadly on diverse topics such as measurements of magnetic moments with molecular beams, study of molecular structure and motion in solids, atudy of chemical honding, applieations in biology and medicine, and uses in masers and in radio-astronomy, A unified picture of the magnetic resonance phenomenon is presented at the level of a firseyear graduate student meeting the subject for the first time. An inquisitive reader is likely to want to learn more after Professor Bloembergen's interesting review, but the list of references is unLikely to help him bridge the gap between this lecture and the advanced work of specialilists. The fourth lecture, by F. Bitter, deals with Flows in a Steady Plasma. This paper is disappointing, for although Professor Bitter ~ o i n t sout how widelv the concept of pl&mas is found in astropiysics and the physics of the upper atmosphere, and although he briefly mentions the effects of magnetic fields upon plasmas, he confines himself largely to the rather prosaic study of the low-pressure mercuryargon discharge. In summary, the hook does little to unify and broaden the wide interests in materials science, being for the most part too specialized and with too few topics to interest the general reader in this interdisciplinary field. Readers with special interests, particularly in physical chemistry of polymers, will find the book stimulating.

W. P. SLICFITER Bell Telephone Laboratories Muway Hill, New Jersey

Chemical Applications of Group Theory

F.Albert Cotton, Massachusetts Institute of Technology, Boston, Massachusetts. Intencience Publishera (a division of John Wiley and Sons, Ine.), New York, 1963. ix 295 pp. Figs. and tables. 15.5 X 23.5 cm. $12.50.

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It is a pleasure to tell you about a new book bv Professor F. Albert Cotton. The hook is about chemical applications of group theory, and, strange as it may be nowadays, the title describes its contents.

In the preface the author claims that the hook is of the type which can he read in bed without a pencil. I tested this out by retiring with the book on three suecessive evenings, and found, much to my surprise, tbat the book was so easy to read and so interesting that I didn't even mind postponing reading Chapter Four of "Another Country." On evening number one, I read the first pert of the hook, which includes the basic definitions and theorems of group theory. Now you've all heard theoretical chemists talk the mumbo-jumbo of symmetry operations, symmetry classifications, reducible and irreducible representations. character tables, etc. By reading the first 86pages of this book, you o m find out, as painlessly as is possible, approximately what is going an. Chapter Three is particularly useful, for in it you learn how to find to which point group B. molecule belongs. A numher of representative molecules are worked out to illustrate the procedure. I was able to follow the d i e cussion in this chapter even though my wife would not allow me to take any models to bed to aid my study of the text (as the author recommends). On evening number two, I read half of the last part of the book, which is on the applications of group theory to problems of chemical interest. I finished the chapters an the use of symmetry in the construction of hybrid orbitals and molecuIsr orbitals. This part of the book should be of considerable value to organic ebemists,since an excellent acwunt is given of the LCAO-MO method as applied to organic m-orbital problems. At the end of Chaptm Seven, the author makes the move toward inorganic applications by summarizing the results of the application of group theory to the problem of bonding in metal sandwich compounds. On the third evening, I first read the chapter (eight)on ligand field theory. The author diaeusses the eonst~etionof the energy level diagrams which are used to interpret spectral and magnetic properties of metal complexes. There are brief but good discussions of the crystalfield, molecular-orbital, ligand-field and valencebond approaches to the bonding in metal complexes. The last chapter is on molecular vibretions, a subject which I have avoided for years. But, knowing that if I Finished I could return to "Another Country" an the fallowing evening, I decided to attempt to read the last chapter. I t went down very well. The chapter gives a. good account of the power of the application of group theory to vibrational problems. In my view, "Chemical Applications of Group Theory" is a first-rate book. It seems to me that seniors and graduate students in most fields of chemistry will ~ r o f i tby reading it. There are minor errors here and there, but they are so trivial tbat they do not deserve space in the body of the review.' There is one final item. The appendix of character tables is a separate pamphlet which is placed in a brown paper pocket in the hack cover of the book. When someone b o m s your copy of the book, be (Continuad on page 114)

Volume 41, Number 2, February 1964

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sure to write your name on the pamphlet as well as in the regular place in the front. of the book. HARRYB. GRAY Columbia University New York, New Y o ~ k

* A few minor oorrections: On p. 172, the proportionality constant between energy integrals and overlap integrals is considerably larger than two electron volts; p. 188, L = 7 should he a K state, since J is skipped over in sssigning letters to angular momentum values; p. 213, the increasein A, on anincrease by one unit in the oxidation number of the metal is usually between 20-110%, not 100-200%; p. 229, both d.t~,s and d,> orbitals can o-bond with the ligands in a square planar cnmplex (not just dXa-,=).

Selected Values of Thermodynamic Properties of Metals and Alloys

Ralph H u l t g ~ a , Raynond L. Ow, Philip D. Anderson, and Kenneth K. Kelley, all of the University of California, Berkeley. John Wiley and Sons, 963 pp. Inc., New Yark, 1963. xi Figs. and tables. 18.5 X 24.5 cm.

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Thermodynamic properties for the "metallic" elements and their binary alloys have been the interest of Professor Hultgren and his group far many years and this volume summsriaes much of their work to "select" values and evaluate the reliability of the available data. In general, each table for an element consists of a review of s t ~ c t u r ddata and phase diagrams, low temperature heat capacities and high temperature heat contents, and vapor pressures a t temperatures up to the normal boiling point. Although ~srenthesesare sometimes used to indir:rte eatrxpol:fiti.m, tlrta ir not s l w a y s dcme and rlw rr:drr ~ I ~ ~ ~ rrrnernlm ulcI tlut rlo buili~rgp i n t s of d m w n t ? :.I 3011U-.i00Oo1< have been reliably measured. For the various alloy systems the presentation includes a phase diagram, low temperature and high temperature heat contents. vaoor oressures and/or other a8 a. function of composition. Notable missing elements in this tahulation are boron, carbon, and silicon and, therefore, the metallic borides, carbides, and silicides of so much current interest have not been covered. Since this field is one in which there is much current sctivity, it is apparent that not every recent paper has been evaluated and a date on each table indicates when the printed tables were assembled in find form. In most cases the tables present an evaluatiun of all the data up to 1960 and in some cases, up to 1961 or 1962. There are, however, a significant number of tables which only bring the reader up to 1956 or 1858. For instance, the table on Zr is dated November, 1956. I n addition, the coverage of elements is essentially random. For example, there have

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Journol o f Chemical Educution

been at leaat three laboratories recently concerned with the vapor pressures of the platinum metals and some of these data (1961) are considered far Ir, Rh, and Ru but the review of P t (dated July, 1960) cites only the 1927 data of Langmuir. In summary, this book presents an extremely useful summary of reliable thermodynamic data. Since new data are being continually produced and there are so many binary alloys, tbe publication is somewhat incomplete and not quite current but there has been a personal, critical review of each set of data finally presented.

Professor Lynton has provided a useful reference work for persons who are interested in superconductivity hut who are not themselves involved in theoretical work on the subject. For this reviewer, oriented toward experimentd work, the book would have been immensely improved if more space had been devoted to experimental results. Half of the volume, a t least, could have been used in a systematic presentation of data, from which examples could have been drawn later for comparison with theory. The theoretical chapters tliemselves would be better if more serious effort had been made to discuss critically the contributions and limiJOHNL. MARGRATE tations of the various theories, espeeidy Rice Uniuersity the currently most useful BardeenHouston. Tezas Cooper-Schrieffer version. In conclusion, "Superconductivity" is recommended as s. handy summary and 8OUrCe of reference for the student who wishes to make s study of supereonductivity in general or of some particular asSuperconductivity pect of it. The newcomer who uses it E. A. Lpton, Rutgers University, New bv itself is not likely to learn much more Bmnawick, Xew Jersey. John Wiley than the language of the field. and Sons, Inc., New York, 1962. ix J. J. FRITZ 174 pp. Figs. and t,ables. 13 Tbe Pennsylvania State University X 18.5 cm. $4.50. University Park In the past twenty years, the topic of superconductivity has been given an amount of attention accorded few other fields of physics. Professor Lynton has indeed undertaken an ambitious task The Shock Tube in High-Temperature in trying to summarize in a thin volume Chemical Physics both its experimental and its theoretiod A. G. Gaydon, University of London, aspects. He has succeeded much better England, and I . R. Hurle, Cornell with the latter than with the former. Aeronautical Laboratory, Buffalo, New Lynton recommends his book as an York. Reinhold Publishing Corp., New introduction to the field of superconduc307 pp. Figs. and York, 1963. ix tivity or as a basio reference to its present tahles. 14.5 X 22 em. $15. state. A brief opening chapter discusses some of the basic experimental observaDuring the years since the war there tions. Almost all of the remainder of the has been a. rapid increase in the amount of book is devoted to summarizing the variresearch on the properties of high temous macroscopic and microscopic theories perature gases. This has been m d e of superconductivity, with selected expossible to a significant extent by the perimental results given by comparison. widespread development of shock tubes A closing chapter on Superconducting Dewhich thus became of special interest to vices mentions briefly a number of present chemists. Geydon and Hurle show a uses for superconductors, but elaborates practicing research worker how to go about only on their (relstivelg minor) use in producing and studying shock waves in computer circuits. his laboratory. This is in many ways a The concise summary of various theohow-to-do-it book with plenty of helpful ries, with the many references to the literahints about techniques and procedures ture, will certainly be useful to those who but with Less concern about the theoretical wish guidance in studying the past and background. For instance detailed expresent state of the theory. It is reasonamples are given for the calculations ably complete, although the important which relate the speed of a shock wave to early theoretical work of London, Gorthe properties of the hot gases behind it; ter, and Landau is given only very cura t the same time many of the formulas are sory treatment. This reviewer was surjust written down with little or no indicaprised to find out that the late F. London's bion of where they came from. full account of his theory, given in his The book may be divided into three book "Superfluids," is nowhere menparts. First there is a description of tioned, despite the f a d that it formed a shock waves in ideal and real gases with large part of the base for later work. Of particular application to shock tubes. greater concern, the author greatly overNext there is a thorough discussion of the states hia case where he implies that a. design and construction of shock tubes and reader new to the field could expect to of the techniques used for measuring follow the summaries of the various theshock speed, temperature, pressure and ories with understanding. To do so, density. Finally, several chapters are he would not only need a good knowledge devoted to the results of shock tube work of eleetrodynsmies and of modern theory grouped under relaxation processes, of metals, but must already know the spectra and chemical reections with definitions and physical meanings of special emphasis on detonations. terms used in these theories, few of which are explicitly defined in the book. (Continued on page A126)

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