Molecular Beams and Reaction Kinetics (Schlier, Ch.)

mare detailed than what poeple have imagined in the otherwise so fertile prewar years." The present book is devoted to new information about the use o...
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rescue a topic from obscurity, a drawing was created to fill the gap." It is not always certain that the gap has been general references a t the end of each filled, even though in some cases the legend chapter and the extenswe subject index. occupies more space than its figure. I. M. KOLTHOFF Seldom have so many words been used Uniuersitg of Minnesota where fewer would suffice; for an exmple, Minneapolis, 56455 see the footnote p. 141. To illustrate simple axes of rotational symmetry one Molecular Beams and Reaction Kinetics and a half pages are devoted to diagrams showing polar views of the earth assuming Edited by Ch. Schlier, Universitrtt its surface to be s. featureless ocean except Freiburg. Academic Pre.98, New York, for two, three, four, or six North American 1970. xvi 437 pp. Figs. m d continents. The reviewer finds i t difficult tables. 18 X 25 em. 822.50. to understand why it should be considered necessary to explain a n paper concepts The editor states in the introduction of which are much more easily appreciated the book: "Moleculsr beam techniques from models. If there are hrmc.hes of have already set new standards for the science which cannot be undentood by accuracy with whieh intermolecular pomost people without the use of models tentials can be determined. The applisurely they include crystallogrsphg and cation of the molecular technique to strueturd chemistry; the current fashion reactive scattering, i.e., to the study of to replace "solid geometry" in high simple chemical reactions, has already school curricula by more "sophisticated" produced information about the dynamics branches of mathematics has done nothing of some of these reactions, which is far to help the student to think in three mare detailed than what poeple have dimensions. imagined in the otherwise so fertile prewar years." The present book is devoted to The section on the principles underlying new information about the use of molecucrystal structures is prefaced by the lar beam techniques applied to problems remark that crystals are divi~ibleinto two of reaction kinetics. Topics discussed major types, molecular, and non-molecuinclude elastic and inelastic scattering, lar crystals, and we are told that molecular ionic reactions and electron reactions crybtals consist of a regular packing of (excitation transfer), nonbeam methods molecules, a molecule being analogous to a "fraternity of atoms." Ionic crystals and the connections between beam and nonbeam results, case studies of H+- and are discussed in terms of ionic radii and H-transfer, computation of energy surradius ratios and the closest packing of spheres; there appears to he no mention of faces and trajectory studies. A heavy weight has been given to computation of lattice energy. A short paragraph on energy surfaces and trajectory studies "potential energy and tangency" conbecause these methods have yielded so cludes, "In summary, as first said b y the much insight into the dynamics of small great Norwegian geochemist, V. M. systems. Each topic is written by a Goldschmidt, a cation cannot 'rattle' different author who is an active research within its niche among the anions in a worker in the field. structure." The structures of simple This book is a very useful review ionic (?) crystals A d , are discussed volume, which can be recommended to solely in terms of Pauling's "rilles" ("their beginnem in the field and any readers who structures largely follow the p1,inciples wish to assess the successes and limitations governing the structures of ionic crystals of molecular beam techniques applied to as elucidated by Linus Pauling.") and problems of reaction kinetics. However, Lima-de-Faria's classification of s t r u o if one is interested in the detailed technical tures!! There is an unusual sequence of aspects of molecular beam experiments, he topics in Chapter 9, of which the following may have to look for other b o o k in an example: Pauling's first rule, the CsCl and PjaCl strnctures, Pauling's YUH KANCP A N second rule, the NiAs structure. UnBoston College fortunately Pauling's rules represent a Chestnut Hill,Massachusetts 08167 codification of principles found useful in determining the structures of complez Crystallography and Crystal Chemistry: ionic crystals, and they have little releAn Introduction vance to t,he structures of simple ionie crystals. The NaCl struetore is deF. DonaTd Bloss, Virginia Polytechnic scribed under ionic crystals and a very Institnte and State Universit,y, Blacksincomplete list of compounds with this burg. Holt, Rinehart, and Winston, structure is given, omitting such com545 pp. Inc., New York, 1971. xii pounds as InSb, UC, UN, UO, LaS, Figs. and tables. 16.5 X 24 em. CeS, etc. Even though the list is re$5.25. stricted to the more ionic crystals with One-third of this hook is devoted to this structure it is stated that several "classical" crystsllography (point-groups, have ionic radii lying outside the range morphology, space-groups), approximately (0.73-0.41) for octahedral coordination. one-third to crystal chemistry, and the In fact this is true of 11 of the 35 examples remainder to physical properties and an listed, and the radius rittios range from introduction to X-ray eryslallography. 1.26-0.35. The author admits that "facThe treatment throughout is descriptive tors in addition to the radiufi ratio concept and non-mathematical. An extraordinary must operate" but the subject is not amount of effort (and money) bas been punued further. Nevertheless 8'/* pages p u t into elaborate illustrations in accordare devoted to a table of ionic radii, ance with the statement in the Preface: though lattice energy and the names of "Where words alone appeared unable to Born and Madelung are not mentioned.

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I n summary: this hook contains s considerable amount of factual informrttion which has been painstakingly compiled from standard textbooks and review articles. It is extremely verbose, and the arrangement of material in places is such as to confuse rather than enlighten the student. I t is good to have questions and answers a t the end of each chapter, though they range, in the same chapter, from "what is the weight percent of N a in NaCI?" to a question on the twinning of felspars. The topics covered by the text would require a t least one year of undergraduate time. There me probably few institutions in this country that include such an undergraduate course, and it is difficult to see to what class of students such a course would cater. Some acquaintance with much of the material is necessary for the student who intends to specialize in the chemistry or physics of the solid state, but the detailed knowledge of crystal morphology is probably necessary only for students of mineralogy. I t is doubtful whether many undergraduates would have the time (or inclination) to use the lists of references or recommended reading, which inchlde standard textbooks, a paper in Tsehennaks Min. Pet?. Mitl., and the space-group tables of the International Union of Crystallography. This hook cannot be recommended as "a text that is easily understood by undergraduates an their first exposure to crystallography and crystal chemistry," though parts of it may be useful to teachers who do not have a t hand the standard texts from whichit is compiled. A. F. WELLS University of Cmnedieut Slavs, Conn. 06868

Topics in Chemical Instrumentation: A Volume of Reprints from the Journal of Chemical Education

Edited by Galen W. Ewing. Chemical Education Publishing Co., Easton, Pa., 1971. 329 pp. Figs. and tables. 28.5 X 22.5 em. $7.50. I t is gratifying to see the selection of articles which have appeared in the Topics in Chemical Instrumentittion column in OF CHEMICAL EDUCATION the JOURNAL reprinted in hook form. These articles were originated in 1959 by Seymour 2. Lewin of New York University to present "the basic principles, cheracteristics, and limitations of chemical instrumentation. . . ranging from balances and burets to servamechanisms and spectrometers." In 1962 the column was opened to guest authors, and in 1967 Galen W. Ewing, of Seton Hall Universit,~,became editor of the column. Under both editors emphasis has been on commercially available equipment with articles typically providing summaries of design features of current offerings of mannfacturerr, approximate costs, and a. critical discussion of advantages and disadvantages of the various features. More recently, the scope of the column has been broadened to include "topics that are of practical importance to (Continued on page AS18)

Volume 49, Number 5, May 1972

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