Huckel molecular orbitals (Heilbronner, E.; Straub, P. A.) - Journal of

Huckel molecular orbitals (Heilbronner, E.; Straub, P. A.). David L. Powell. J. Chem. Educ. , 1967, 44 (6), p A554. DOI: 10.1021/ed044pA554.1. Publica...
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BOOK REVIEWS tions, molecular symmetry, and selection rules. Chapter Four contains a fair bit of information on characteristic group frequencies, but the arrangement and format of the tables is not conducive to quick referenee. The introductory theoretical discussion of electronic transitions is made to appear more complicated, and probably unnecessarily so, by the use of Greek symbols fi and 6,for atomic and molecular orbital wave functions. Perhaps this is merely a subconscious attempt to compensate for the largely empirical nature of ultraviolet spectroscopy. An outstanding feature of Chapter Six is Table 6.2 (pp. 192-194), correlating the spectral characteristics-in NMR, IR, and UV-f some important functional groups. The book as a whole suffers somewhat from poorly drawn schematic diagrams, with respect to instrumentation as well as to theory. I t could be further improved by a more detailed index, dthough Table 6.3 (pp. 1950 on Information Sources within this volume is most usefrd. On the whole, thisvolume can be recommended as a textbook (or for self-teaching) for an introduotory course on molecular spectroscopy as applied to organic chemistry. WALTERJ. LEHMANN University of Massachusetts at Boston Hiickel Molecular Orbitals

E. Heilbronner and P . A . Slraub. Springer-Verlag New York, Inc., 1966. 824 pp. Tables. 25 X 31 cm. Looseleaf ring binder. $18.

ing types of compounds: linear chains containing 2 to 22 atomic orbitals, single rings containing 3 to 22 atomic orbitals, all possible systems containing from 4 to 7 atomic orbitals, selected systems containing from 2 to 10 f u e d rings (all the rings contain 6 atoms), some branched aromatic systems, and some systems containing 5 and/or 7 membered rings either instead of or in addition to 6 membered rings. The book also contains a listing of the FORTRAN program used to obtain these results. The information given for each molecule includes the fallowing: energies, coefficients, bond orders and chasge densities, atom-atom polaririsabilities, bond-atom polarizsbilities, and bond-bond polariaabilities. I n all the calculations, d l the coulomb integrals have been assumed equal and sll resonance integrals between bonded atoms have been assumed equal. It should be noted that this "book" is not bound; rather the pages, all 824 of them, are contained in a loose-leaf ring binder which is very unhandy to use. The pages of the review copy had a miniinches, so it appears mum margin of 11/~ that one can have the "book" bound oneself if one so desires. DAVIDL. P o m m College of Wooster Wooster, Ohio

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Journol of Chemicol Education

The Analysis of Physical Measurements

Emerson M . Pugh, Csrnegie Institute of Technology, Pittsburgh, and George H. Winslow, Argonne Nstional Laboratory, Argonne, Illinois. Addison-Wesley, Reading, Massachusetts, 1966. ix 246 pp. Figs. and tables. 15.5 X 23 cm. Paperbound. $4.75.

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The subject of "statistics" is dual in character. One side presents the mathematical concepts; the other uses those concepts as an aid in the interpretation of experiments. Snedecor's book, "Statistical Methods," and s. host of others thrtt followed dealt with the latter role in sgricoltnre and other areas of biology. Numemus texts on the mathemetical aspects of "statistics" are available. As new books appear dealing with the subject of statistics they are criticized for being (1) incomprehensible to nonmathemat,icians, if they deal with the m a t h e matics, or (2) "a. trivial cook hook," if they contain no mathematics but attempt to relate statistical mebhods to experimentetion. Consequently nearly every baok that appears contains in its preface or in its advertisements glowing accounts about how this text will serve the experimenter and satisfy the mathematician. The representation of the present book under review is no exception. The Preface contains this statement, "Our purpose is to emphasize objective, practical, and appropriate numerical caleulstians rather than present a. study of theory." Elsewhere it is stated that the authors consider the hook ss s. text and B useful guide for professional experimentalists. First impressions of this book lead one to believe that the authors have indeed finally achieved 8. balance between the methemiltical and practical snalysis. After 142 pages (out of 204) of the mathematical backeround of standard deviation and the nsml distributions one comes to s. section entitled Introduction of Ststistied Analysis. Here one hopesto find something that will make the book a "useful guide far the experimentalist!' Unfortunately nearly all one finds is more of the mathematics of the chi-square, "t," F, and the correlation coefficient. Same examples of experimental oroblems are included but these would

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experiments. Consequently, the title of the book, "The Analysis of Physics1 Measurements," i~ a misnomer. What the book really represen& is a review of the fundamentals of statistics, from a mathematical point of view. I n this regard it is a very good book. The authors have presented the mathemsties in a clear fashion that is easy t o follow. Any student with a. good background in mathematics through elementary calculus would find the text quite r e warding. I t would provide 8. solid basis for further explomtion of the mathematical basis far statistical methods. The book is printed in a readable format and is reasonably priced (although it is paper backed). If one were contemplating giving a course dealing with st,atistics to m y group of students, and such s. course were not available in the mathematics department, then this baok would be useful. It would also be

useful as a. supplement to s. course dealing with analysis of measurements (not neeessarily physical), but only as mathematical background because the authors have not concerned themselves with the role of experimentation in investigative science. The authors have failed to convey the concept of experimental error as the interaction of "treatment" with a random e l e ment in the population. Failure to perceive this principle is proba,bly the primary cause for physical scientists to be slow in accepting the use of probability statistics as they are practiced by biologists. Perhaps because of this the authors present a curious concept of "error." They relate "accuracy" to systematic errors and "precision" to "chance." It may he just semantics but this reviewer considers sccuracy and precision as synonymous and related to errors in the technicality of measurement and prefers the word reliability to relate to chance. The authors have not sufficiently exploited the role of randomization in experimentation to allow the stndent to differentiate between random variation and "technical" errors in measurement. In fact, the subject of design is completely absent in this baok, and design, analysis, end interpretation in experimentation cannot be separated. To summarize: This book is an excellent presentation of some of the elementary mathematics of statistics. I t would serve a useful role as s. reference for a. beginning mathematical ststisties course or it could mrve as background material for a met,hods course in sbatistics for mathematically competent students. I t is in the words of the authors, "not so much utilitarian aa instructional." C. R. WEAVER Ohio Agricultural Research and Development Center Wooster

The Noble Gases

Isaac Asinum. Basic Books, Inc., New 171 pp. Tables. York, 1966. x 14.5 X 21.5 cm. $4.50.

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Isaac Asimov has written a dramatic and wideranging account of the discovery, properties, and applications of the noble gases. Although the book is directed toward the interested layman or novice, it can be read with pleasure and profit by anyone who desires a quick survey of the most important aspects of noble gas chemistry. The emphasis throughout is on understanding the properties and various phenomena associated with the gases; thus the discussion of the ionization potentials of the gases is accompanied by a simplified, though meaningful, explanation of the experimental technique and theoretical significance of the phenomenon. Chapter 1 covers the early period of investigation of gases, Cwendish's discovery of a small bubble of pa3 (armn) which does not react with oxygen in-an electrical discharge, Lockyer's discovery of helium in the sun, and Hillebrand's near discovery of helium in uraninite. Chapters 2 and 3 give a detailed account of Rayleigh's discovery of t,he discrepancy in the density of nitrogen, and Ramsay's isolation and charactwim-