Molecular thermodynamics. An introduction to statistical mechanics for

mentary quantum mechanics for the chemist. PHILIP E. STEVENSON. Worceste~ Pol.yteehnie Inslitule. Worcesler. Massachusetts 0160g. The Periodic Table...
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elements, transitional elements, innertransitional elements, electro positivity, valency and salt-like compounds. Section B.2 interprets these concepts in modern one of its two major weaknesses. I t s terms, and introduces further concepts for explanations and derivations are rather later use. terse and probably would be rough going Section A.3 deals with, in the author's for must students. Moreover many imopinion, the best empirical form of the portant topics are introduced with inmodern Periodic Table, while Section B.3 sufficient experimental background and no presents electronic justification for t,he explanations for their importance. The proposed form. Sections A.4 and B.4 other weakness is s, propensity for overdeal with the general struct,ure of the elegance. For example: the valence Periodic Table as a whole, detailing the bond description of 1% is given as a linear trends among the elements and their hycombination of two dderminants whose drides, oxides and halides. Section A.5 amounts to a detailed consideration of the Groups designed to show absent. the "sweep and unity" of t,he Periodic The initial attractiveness thus fades System. This section contains a wealth of in the light of close examination. What information prsented concisely and should seemed t o be an inexpensive text,book be read in one sitting. By doing so, the wit,h everything in i t turns oot to be little reader will be able to see how and why the more than a. good review uubline of elearrangement of a. vast amount of informamentary quantum mechanics for the tion by Group and Period is essential for chemist. B.5 clear understanding. Section PHILIPE. STEVENSON amounts to a detailed theoretical interpreWorceste~Pol.yteehnie Inslitule tation of the trends within the periodic Worcesler. Massachusetts 0160g groups presented in Part A. Sections A.6 and B.6 deal with the experimental evidence and theoretical justification of special topics, including diagonal relationships; contrast of the first The Periodic Table. transitional series with the second and Experiment 8 Theory third transitional series; similarity of the J . S . F. Pode. Mills & Boon, London, second and the third transitional series 263 pp. Figs. and tables. 1971. xix (the Lant,hanide Contraction); and the 23 X 1,; cm. £1.12, Softbound. chemist,ry of the Lanthanides and Actinides. This paperback book is a. deliberat,e atSection A.7 includes approximately 150 tempt on the part of the author to demonsimple experiments which demonstrate, strate the dynamic interplay between though not in a comprehensive manner, theory and experiment and, further, to group properties and support the factual show how greatly the imaginative insight material presented in Part A. The exof Dmitri Mendeleev has influenced chemperiments have been chosen t,o be ~ m ical thought. In this reviewer's opinion, ambiguous and easy to perform. he has succeeded admirably. The author has intended this paperback The approach is both unique and excitbook for studtints and teachers of cheming, with the book divided into two parts. istry a t the Advanced and National CertifPart A (Experimental) is an empirical icate levels in Great Britain. However, account of the great diversity of experithis reviewer believes that t,hebook will be mental facts available, although the inof immeasurable value to students and formstion presented is deliberately conciae, teachers alike as s. supplement in introstressing regular trends within the Periodic ductory chemist,ry and as an excellent Table. Part B (Theoretical Interpretareview for students of intermediate or tion) on the other hand, is an interpretaadvanced inorganic courses in this country. tion of the material presented in Part A in terms of modern valency theory. Each RICHARD W. NEITHAMER numbered section in Part A has a. counterEckerd College part in Part B. (forrnedy Florida Presbyterian College) Part A of the book could stand on its St. Pelemburg, Florida own merits, although, as the author admits "a diet of fact undilut,ed by theory tends to be somewhat arid." Part B, on the other hand, needs to be read in conjunction with Part A. Molecular Thermodynamics. An InfroThe Introduction to Part A discusses durtion to Stotlrtical Mechanics for the historical background concerning t,he Chemistry nature of chemical families, while the Int,rodaction to Part B deals with the doJohn H. Knoz, University of Edinvelopment of the concept of orbitals and burgh. Wiley-Interscience, New York, electron distribution within atoms. 1971. xiii 264 pp. Figs. and tables. Section A . l describes the nature and 23.5 X 15.5 cm. 911.95. function of a scientific hypothesis and the predicted successes, anomalies and apThere is a. need for an introductory text parent failures of Mendrleev's ~ystem. in statistical mechanics a t the juniorSection B.l shows how modern theory senior level, designed for chemistry stuaccount,^ for both the successes and failures dents whose interests are msinly experithe system experienced. Section A.2 premental. Such s. book should develop the sents empirical definitions utilized in the underlying formalism in a. physically remainder of Part A including main group sound, but mathematically uncomplicated,

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Journal o f Chemiml Education

way and then proceed to treat a wide variety of topics of chemical interest. The author has attempted this with mixed success. The applications are generally well chosen; there are drawbacks to his treatment of the fundamentals. The first half of the hook is devoted to a review of quantum mechanics and thermodynamics and the development of elementary ensemble theory. The level of presentation is most uneven. The mathematics is clearly detailed and would present no problem to the prospective student. The author's treatment of some subtle problems, while not manifestly incorrect, is certain to mislead beginners in this field. The seetion on quantum mechanics discusses the simple model systems necessary for later applications to crystals and gases in an interesting way, leaning heavily on the de Broglie postulate. I t then strays into a discussion of indistinguishability and its relation to Fermi and Bose statistics. By including hydrogen atoms as bosons, the author misses the point that the statistics can he applied only to particles that maintain their identity. I n a gas of hydrogen atoms it is impossible to mociate a proton with a unique elect,ron; collisions between atoms will certainly allow electron exchange. The presentation of ensemble theory is simple but incomplete. I t is based on the microcanonical postulate that all systems in the ensemble with the same macroscopic parameters are equally probable. However, nowhere is it emphasized that the ensemble is constructed to mirror our basic lack of detailed informstion about the thermodynamic system. I n the t r e a t ment of the canonical ensemble, the syst e m of the ensemble are assumed independent and of a fixed energy. The sense in which these assertions can be correct and yet have the systems coupled to a heat bath is not discussed. Such a discussion is necessary if the student is to understand why this form of ensemble theary is only meaningful far systems containing many particles. In his quest for simplicity the author has ignored some of the basic assumptions of statistical mechanics. The applications are generally worthwhile. The t o ~ i c treated s are the t,hermo-

rium, absolute reaction rate theory, and the Einstein model of ideal crystals. The interesting features are the detailed consideration of internal rotation and the care with which numerical caleuletions are worked out. This latter is most helpful to anyone who wishes to learn how to use spectroscopic and structural data to compute thermodynamic properties. The treatment of the molecular partition function for homonuclear diatomic molecules is in error; the symmetry of the electronic wave function is significant but the vibrational wave function is alwaytys unaltered by an exchsnge of nuclei. The thermodynamics of the dissociation of fluorine is discussed in detail. It points up clearly how statistical thermodynamics can be used effectively to determine bond energies accurately even though the thermochemical data is not particularly precise; (Continued on page A60.9)

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