Electrons and chemical bonding (Gray, Harry B.) - Journal of Chemical

Electrons and chemical bonding (Gray, Harry B.) F. A. Cotton. J. Chem. Educ. , 1965, 42 (5), p 292. DOI: 10.1021/ed042p292.2. Publication Date: May 19...
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follows that the number of those who may actually be included in that select group Paul R. F w y , Colorado State University, of scholar-teachers who fulfill the above Fort Collms. 3rd ed. PrenticeHall, criteria is not large. I think that for Inc., Englewoad Cliffs, New Jersey, Harry Gray this book, together with his 747 pp. Figs. and 1965. xviii contributions to the research literature, tables. 17 X 23.5 cm. $8.95 assures hi membership in this select company. The purpose and descriptive approach I enjoyed reading the book and though of earlier editions are retained in this new I consider mvself conversant with the edition. Chanxes have been made largely subject, I must confess that I learned a to improve clarity of expression, legibility, few things from it. I shall offer presently utility, and logic of presentation. The a few criticisms, mostly omissions, hut two chapters on atomic structure and the first I want to state that I consider this an periodic clt~ssifieationhave been moved excellent book, characterieed by clarity, ahesd of the two chapters on states of accuracy, and grace of style. I know of no matter. Two unified ohapters on organic better guide to the neophyte in this very chemistry now inolude the topics of important but easily mistaught subject. polymers, fuels, and explosives. The excellence of the book also owes Some new terms and ideas have been much to the handsome, timely, and introduced smoothly but cursorily so that modestly priced embodiment given it by they do not play a major role in the the publisher. I assume that in offering development of the text. These include this volume a t a. price of only four dollars dipole moment, conjugate acids and bases, less five cents (why not $4 instead of the nuclear binding energy, bond energy, Filene's basement-style price of $3.95; electron affinity, entropy, hydrolysis conor, why not go all out and make it $3.99; stants, nuclear structure models, lyabut I digress) the publisher is counting phobic and lyopbilic colloids, quantum on a big sale. I think the book deserves a numbers, X-ray diffraction patterns of big sale, and I hope and believe it will crystals, and the dielectric constant, have one. which, unfortunately, is defined incorrectly. Beginning with the electronic structure Satisfied users of previous editions will of atoms, the book proceeds to the MO be happy with the inclusion of the uptreatment of diatomic molecules, linear dated features of the reference library, triatomic molecules, planar and then readings, films, and lecture demonstrapyramidal molecules with three-fold symtions. The 1995 student exercises spread metry, tetrahedral molecules and then over the 36 chapters represent an increase bent triatomic molecules. Next comes a of about 41% over the second edition. brief and elementary but surehanded The appendix includes a brief outline of a treatment of *-bonding in organic moletypical qualitative analysis cation scheme cules and finally a smooth and expert with references to appropriate sections introduction to the MO, CFT, and LFT of the text. theories of transition metal complexes. Despite the author's claim that "the This last chapter does a very good job order and development of topics are of explaining the relationships among designed to arouse and hold the student's these theories and also their relation to the interest regardless of his background valence bond theory. Throughout, the a t the secondary school level," it is doubtarticulate and reasoned explanation of ful that a student who has had a rigorous theory is embellished with appropriate high school course in chemistry would citations of facts and data and tempered find much to challenge him in this book. with the necessary reservations and However, for those who can justify the cautionary remarks which the inherent use of the traditional descriptive approach crudity of simple LCAO-MO theory to beginning college chemistry, this is a properly requires. There are also a thorough text full of useful aids to both number of interesting and instructive student and teacher, handsomely proquestions and exercises provided. duced, and well worth consideration. The level of the book is such that it MILTONK. SNYDER mieht be used anvwbere on the undergrndoatc level depending nu h,cd wndiThe Colorado College tio~.sandcustoms, hut 13mhure 111x1most Colorado Springs first year graduate students rould hewfir from reading it. Thereare perhaps those who may object to the fact that the MO approach is used Electrons and Chemical Bonding almost exclusively with only occasional asides concerning the YB method. I Harry B. Gray, Columbia University. personally feel that considering the manW. A. Benjamin, Ino., New York, ner and spirit in which this is done it is all 223 no. Fies. and tables. 1964. xv to the good. One small book cannot be 14 X 22 em. Clbthhoun>, $8; paperall things to all men and, at present, the bound, $3.95. MO approach seems to be the best single choice. Most of us in the teeohing game (if I may be permitted a slight degree of There are some omissions which do irreverence) cherish two cardinal aspects strike me as being detrimental, but these of our professional amnu? pmpre, namely, can easily be remedied by the teacher. that we know our subject and that we The interelectronic shielding effects which me responsible for the deviation of the know how to put it across to the students. actual order of filline orbitals from the The first may well be true in a high perorder of orbital energies in the hydrogen centage of cases, but the latter is more stom we not explained. Multicenter often a conceit than a fact. Thus it College Chemistry

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Journal o f Chemical Fducofion

bonding as in the hydrogen bridges in boranes and the methyl bridges in alkylberyllium and alkyleluminum polymers is not covered. This could so easily have been done with the MO picture of the bonding in BeHl as a point of departure that it seems a oitv to have missed the and aromatic rings to transition metal atoms would a h have been easily added on the basis of what is already given. However, to conclude, this is an excellent hook which deserves a place in every undergraduate curriculum. F. A. COTTON Facultad de Ciaeias Ezactas y Naturales Universidad Naciaal de Buaos Aires Argentina

Chemical Bonding

Audrey L. Compania, Illinois Institute of Technology, Chicago. McGraw-Hill Book Co., New York, 1964. vi 155 pp. Figs. and tables. 13.5 X 20 cm. Clothhound, $4.50. Paperbound, $1.95

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FoIlowing an introduction to quantum concepts and atomic orbitals, this short textbook discusses in a nonmathematical fashion covalent, ionic, and metallic bonding, van der Waals forces, and crystal field theory. These topics are treated at a level somewhat more advanced than that found in the most commonly used college chemistry texts. However, the presentation should be suitable for use by good high school students and most college freshmen. An authority on chemical bonding might be dismayed by the informality of the text, but the beginning student should h d it readahle. Its presentation of some topics such a s metallic bonding and crystal-field splitting is unusually good. After each chapter there are s. number of exercises, many of which are novel; these exercises with their answers considerably enhance the value of the hook as a text. The book differs from the similar paperback text by Ryschkewitsch primarily in its use of a molecular orbital approach to covalent bonding in contrast to the traditional Lewis dot structure approach. "Chemical Bonding" also di5ers in including topics such as crystal field theory and metallic bonding. In attempting to discuss atomic orbitals and chemical bonding in elementary terms, it is difficult to avoid making statements which, if they are not dehitely inaccurate, are a t least misleading. A number of such statements are present. The only explicit conceptual ermr found by the reviewer is the statement on page 21 a 1s orbital there will that "within then be a single fumy spherical shell of high electron density. . ."; this misconception could easily arise from the inaccurate labeling found in Fig. 3-3. In several places the shapes of orbitals are not presented as accur&ely as they should be in a text on bonding. In fact it

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