Quantum organic chemistry (Higasi, Kenti; Baba, Hiroaki; Rembaum

Quantum organic chemistry (Higasi, Kenti; Baba, Hiroaki; Rembaum, Alan). Frank L. Pilar. J. Chem. Educ. , 1966, 43 (7), p 395. DOI: 10.1021/ed043p395...
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when sample avdabilit,y is not a limiting factor. Although these techniques require some skill and close attention to detail, they are rarely so difficult that only a speeidist can use them. That this thesis is not new is well known to readers of the late Professor A. A. Benedetti-Pichler's book, "Introduction to the Microtechnique of Inorganic Analysis," (reviewed in J. CHEM.EDUC.20, 51 [1943]). Professor Korenman's book leaves the reader with the same impression. In discussing scales of working, the author defines ultramicrotechniques as thoae applied to quantities of a few micrograms or less, as well as t o solution volumes not exceeding 0.05 ml. A microscope and a micromanipulator are often required to work with such small quantities. The high surface-to-volume ratio of microliter qnantities of solutions greatly enhances problems such aq adsorption, atmospheric contamination, or loss by evaporat,ion. The minimization of these effects is admirably discussed. Chapter 2, which describes general apparatus and techniqueq, is strongly reminiscent of Benedetti-Pichler's t r e s e u#r!.t. .\I lloir pmn1 i l IW~IIIII.. dwiou. 111x1I'nic:or K l m ~ l t n n ' rImuk ~ntt!,.dwJ \lodrrn mifor I crogram ha.lanc,es, ultramioropipets, sophisticated miwomanipdators, and other commercially-available small-scale instrw ments are not described and are rarely mentioned. On the other hand, eonstructiond details are given for mast of the equipment,. This extends even to various forms of quarts-fiber microbalances, the constmct,ion of which is described in Chapter 3. Much of the simpler a p paratus is easily fabricated from meltingpoint tubes and thin glass rod. A leas obvious feature of ultramicroanalysis is that much can be done with a small budget, same manual skill, and a considerable amount of patience,

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Apparatus and techniques for chemicalindirator volumetric analysis are described in Chapter 4. The small depth of solution in drop-scde titrations makes the colorchange difficult to detect, so that a high concentration of indicator is used. Indicator corrections, which are highly important in t,his type of work, are extensively discussed and a small but useful selection of a c t d determinations is given. Although the treatment of physiachemical methodq of analysis in Chapt,er 5 is rather thin, t,he reviewer was glad to note reference to the modern and elegant bipotentiometric dropscale technique of Bishop. The book e o n d u d s with short chapters on miseellrtneous techniques and on gss analysis, then a bibliography with 395 entries. Occa~ionslmis~rintsexist. hut there are

out by use.

JOHN T. STOCK Uniuersity of Connectieul Storm

Quantum Organic Chemistry

Keniti Higasi and Hboaki Baba, bobh of Hokkaido University, Sapporo, Japan, and Alan Rembaum, California Institute of Technology, Pasadena. Interscience Publishers (a division of John Wiley and Sons, Inc.), New York, 1965. vii 358 pp. Figs. and tables. 15 X 23.5 em. $13.

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T h k baok contains a. well-organized, lucid description of the mechanics of the pi electron approximation at its lowest possible level of mathematical sophistication. The emphasis throughout is upon the Hiickel molecular orbital spproximation, although some space is devoted to the Slater-Pauling valence bond method. Any organic chemist willing to m e simple algebra should find this book an easy-tofollow guide to the use of the Hiickel method in those areas of organic chemistry where thk approximation is most sueeessful and useful. The authors are very careful in explaining virtually sjtep-hy-~tep how the calculations are done and bow they are applied to a variety of specific, well-chosen problems. The applications considered include the calculation of dipole moments, the interpretation of electronic absorption spectra, the electron fipin remnance speotroseopy of free radicals, chemical reactivity and polymerization reactions. I n their preface, the authors state: "The excellent texts in this field are still beyond the majority of scientists, and Quantum Organic Chemistry should t h e r e fore serve &S a stepping stone to a more If by a more adadvanced treatise." vsnced treatise the authors have in mind a book such a? Daudel, Lefebvre and Moser, "Quantnm Chemistry," then the statement seems fair. However, it is hard to see how "Quantum Organic Chemistly would be of more than minimal aid toward the understanding of treatises such a5 Eyring, Walter and Kimhall, "Quantum Chemistry" or Slater, "Quantum Thmry of Molecules and Solids.'' Although these latter texts are by no means advanced, both require mastery of a, great deal more mathematic2 than many organic ehemisL3 are likely to have or be willing to acquire. "Quantum Orgenic Chemistry" is written a t about the same level as Roberts, "Molecular Orbital Calculations,'' but has a more extensive coverage of applications. I n many respects "Quantum Organic Chemistry" is comparable to Streitwieser, "Moleculrtr Orbital Theory for Organic Chemisk," but is written in a clearer, more readable style and, therefore, is perhaps easier ta comprehend as to mechanical details of calculation. The former aka deals with fewer specific examples but these are treated with greater clarity bhan in Streitwieser. I n mmparisonwithKilragounis, "Introductory Quantum Organic Chemistry," one might say that whereas Kamgounis attempts to explain much theory and illustrate little faot, the opposite is attempted in "Qoanturn Organic Chemistry." For this reason "Quantum Organic Chemi~try"is a much more useful book for the chemirr who wishes to learn to apply some quantum chemistry to actual problem% On the debit side, there are no more than brief references to many of the important theoretical a3pects of the pi

electron approximation, i.e., virtually no attempt is made to place the Hiickel molecular orbital approximation or the Slater-Pauling valence bond method into any sort of proper perspective with r e spect to hasio Schradinger mechanics. The orbital approximation is nowhere defined in a general fashion, the variation theorem is given short shrift ($though the variational energy is stated ta be a minimum, it is not made clear that this energy is an upper bound to the exact energy) and little attempt is made to state precisely what the irr separation problem actually involves. However, it is only fair to say that references to the original literature dealing with such topics are copiously given and appear to he adequate. The book is also marred with numerous examples of rather careless language, e.g., the verb "to resonate" appears several times, and hybridization is referred to as "a basic a~snmptionof quantum organic chemistry." However, it is unlikely that such hlemishesnumerous as they a r e will serio~lslyhinder the reader in acquiring a goad mechanics1 facility in the methodq described. I n the final critique, this is an overall excellent baok which e m be enthusiastically recommended to any chemist who want3 to learn to use a9 much quantum chemistry ss possible without being exposed to the important but mathematically-structured fundaments of quantum theory. The book should be admirably suited for self-study or for use in comes in theoretical organio chemistry where use of simple mcleeulm orbital and valence bond methods i~appropriate. FaANK L. PILAR Uniuevsity of New Hampshire Durham

Supplemental Tables of Molecular Orbital Cdeulationr with a Dictionary of T-Elechon Calculations. Volumes 1 and 2

Andrm Sl~eitwieser,Jr.,University of California, Berkeley, J . I. B~auman, Stanford University, Stanford, California, and C . A. Coulson, Oxford University, England. Pergemon Press, Inc., New York, 1965. 1223 358 pp. Tables. 21.5 X 30 cm. $100 the set.

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These combined volumes present Hiickel molecular orbital calculations for over 600 compounds. The molecular orbital calculations section is limited to hydrocarbons; however. the r-electron section includes some important heteromolecul~% Overlap of data in the two parts is very small. Because the tables are printed directly from ha to graphs of the computer readout, typesetting errors me minimal. Use of the tables and the index scheme %reexplained in the peface along with a brief summary of the mathematical methods involved. Volume

43, Number 7, July 1966 / 395