book reviews (Conlinued from p. 126, Col. 2 ) only if there is a certain stability connected with unpaired spins. The fact that the state of maximunr multiplicity is the ground state is not a result of an unusual type of force between the electrons i e a magnetic interaction); it is a consequence of the form required of the wave function by the Pauli Exclusion Principle. The Principle states that no two electrons in an atom can have the same space and spin coordinates (the same quantum numbers) or alternatively that the wave function representing two electrons with the same coordinates of space and spin vanishes. This means that the value of the function for such a configuration is zero, and the probability of finding such a configuration is zero. Therefore, the implication in the postulate that Coulomb's Law be repealed is unnecessary. Coulomb's Law may be kept, and the repulsive forces between two electrons considered to vary inversely with r regardless of spin. The paint is that two electrons of opposite spin can be in the same region of space while two electrons of the same spin tend to woid the same region of space. The occupancy of the same spsce results in a greater repulsion between electrons of opposite spin than between electrons of the same spin. Thus a. singlet state has a higher energy than a triplet state. Spin correlation (the name given to the tendency of two electrons of the same spin to avoid the same region of space) is required by the Pauli Exclusion Principle; it is not an explanation of the Principle. The correct interpretation of spin carrelation leads naturally to Hund's Rule. This is apparent from the probsloility distribution plots of the singlet and triplet states in Linnett's book (page 14, 15). I n his treatment Luder implies that the reason two electrons of the same spin do not oceuov the same orbibal is a. matter of e w r y ~ r i r . T i is n I . The I'auli I'ri~.iplr crnrw that n wrtniu i,ehnviw vannot be dwrvcd, not t l . ~ tit i i iu~likdy, on energetic grounds. I n section 3.2, Luder suggests that we limit the application of wave mechanics to one valence electron atoms and that the electron repulsion theory be applied to d l other atoms. This suggesbion is followed by (on page 48): "One valence electron by itself in an atom seems to display some characteristics of waves. But the difficulties of the wave concept increase enormously when it is applied to two or more electrons in an stam. A tentative conclusion might be as fallows. First, the less reqtricbed the motion of electrons t,he more evident is their wave nature; the mare restricted their motion the more evident is their particle nature. Second, the larger the number of electrons in the valence shell of an atom, whether isolated or in a molecule, the more restricted is their motion and the more they behave as particles. As a matter of convenience, for the time being, the sssumption will be made that in an isolated 'one electron atom' the wave nature of the electron predominates over its particle nature, and that in an atom with two or
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Journal of Chemical Education
more electrons the particle nature of the electrons predominates over their wave nature." Thus we are led to s. particle model of the atom. The ptlrticle model of the atom is no more attractive now than it ever was. I t cannot explain quantized energies or quantized angdsr momentum. I t has not been successfully used in any quantitative argument. Neither the Linnett nor the Gillespie-Nyhalm method is based on a psrticle electron. Electron distribution in space is essential to the Gillespie-Nyholm argument and Linnett talks of alternative methods of constructing wave functions. Since this hook and the Luder articles were published, a t least two articles describing the construction of models to represent Linnett structures have apThese are of peared in THIS JOURNAL. some value in teaching the Linnett method but they have the inherent disadvantages of most models. The limitations are particularly disadvantageous with this method because they imply a rigid particle model of molecular and atomic structure. From this point of view this method has heen harmful because it appears to he based on the particle electron. I t is not, and we look to Linnett as an authority to determine what he is attempting to do. The following is taken from page 60 of Linnett's book: "In effect the hypothesis presented in this book involves a modification, or extension, of the bssic way of construct,ing the first approximation wave functions for molecules and ions." Originators of new ideas are frequently disappointed with tho way their views are interpreted or put into practice. I t is tho opinion of this reviewer that Luder's book does a great disservice to Linnett and his method.
This paper included caleulatmns using Caulomh's law and the corresponding equation for the force bet,ween magnetic dipoles claiming to show that a t small enough distances electrons of the same spin repel each other much more than do electrons of opposite spin. Professor Luder's experience in both teaching and writing are evident in this book. Although some may disagree with his conclosions, all must agree that his treatment of these proposals is attractive and lucid. The electron-repulsion theory is still incomplete and doubtless will he refined and exbended in the years to come. Meanwhile, this book should help teachers and students t,o an inoreased understanding of some of the perplexing problems of the chemical bond and should encourage now thoughts about proposing solo!ions t,o these problems.
Toledo, Ohio Concepts in Biochemistry
Francis J . Reilhel, University of Oregon, Eugene. McGrsw-Hill Book Co., New 414 pp. Figs. and York 1967. xiii tables. 17 X 24.5 cm. $9.50.
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A short comprehensive text with emphasis on concepts rather than on a.large number of facts is very welcome. As the author says in his introductory chapter, this book is an attempt to present "what I believe t,o be worth discussing a t this time," but in fact it covers all the major fields of biochemistry which have eontrihuted so much to the understanding of biological processes within the past ten years. I t is to Reithel's credit that his book does not start with the usual deseripW.~LTER A. MANCH tion of chemical compounds (carbohyMonlana Slate University drates, lipids, proteins and minerals), but, Bozaan, 59715 after the short introduction, starts with the basis of enzymatic activity, followed by two chapters on mitochondrial enzymes. Further chapters are devoted to glyeolysis, (Conlinued fm p. 126, Col. 3) the pentase shunt, photosynthesis, nitrogen fixation, and transport of sugars and When Professor Luder's book was puh- lipids. Five chapters discuss the anima lished in December, 1967, some aspects of acid metabolism, and four chapters discuss t,hese models seemed to conflict with wave- nucleic acids (including synthesis of pumechanics. Since then, relevant details of rines and pyrimidines). The fallowing "standard" wave-mechsnies have been chapters describe protein metabolism, questioned in two papers by It. E . Powell phospholipids, light-sensitive pigments, (J. CHEM. EDUC.,45, 45 and 558 metalloporyphyrins (iron metabolism, (1968)). I n the second of these papers heme complexes, including cytochromes), Professor Powell shows that the nodes and the biosynthesis of co-factors (flavins, obtained from the ScbrBdinger approximapteridines, coenzyme A and others). The tion do not exist in the relat,ivist.ic wave- last two chapters me on cell membranes mechanics of Dirac. More directly rele- and cell walls and on metabolic networks vant is Professor Powell's proposal of new and their control mechanisms. In an ways of constructing atomic orbitals. appendix, the author gives s. catalog of These are exactly what a t r e required to enzymes referred t,o in his book and arsupport Professor Luder's atom models. ranged strictly according to recommendaI n its discussion of the Paoli exclusion tion of the Commission on Enzymes of the principle, the book disagrees wibh that IUB; this appendix is extremely clear and form of the principle which implies a he- well done and contains, besides the systelief that the principle itself causes electrons matic name and recommended trivial to behave in a certain way. Doctor name, the reaction and appropriate notes Luder's pasibion is that the behavior of covering the specificity and unusual charelectrons is debermined by their awn phy- acteristics of the given enzyme. A short sical properties: their negative charges comprehensive list of pertinent literature and their magnetic moments. At the follows each chapter. September, 1968, meeting of the ACS he (Conlinued n page A118) presented a. paper t,o support his position.
book reviews The book is written in s very readable, flnid style; that some of the problems discussed came out sketchy is unavoidable in a book of this scope, but limited in size. I t is profusely i l l n s h t e d hy graphs and molecular structures of discussed compouuds, iu many cases by ball-and-stick mod& as well as by the Stllarl-Briegleb presentstion. The labter seems to be 1111necessary. According to the author, "Biochemistry may be comidered the chemist's view of biology" (p.2), n, most onnsnal definition: similarly we could define organic c1iemistt.y as imrganie chemist's view of carbon cumpounds, a definition to which nu organic chemists would subscribe! Ileithel's definition is quite different from that used by practically all biochemists (e.g., Karlson: "Biochemistry is one of the life sciences. Its object is to study the phenometrn of life by chemical methods"). Accordingly, the chapters dealing primarily with biological phenomena are the least satisfactory and could have been omitted altogether. The process of growth is much too complicated to be treated on five pages (including graphs and structural formulas) and it is not erclnsively the problem of I)NA and RNA (it is impossible to throw into one basket the various types of growth: multiplicative, auret,ic and secretionary): he does not even quote the most important literature on the subject, like the now classical
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hydrates, and other biologically important substances. Generally, chapters are organized to give an overview and the relative importance of the topic followed by the theory and concepts necessary to underst.and the topic and, finally, specific examples and descriptions. Charts, d i e grams, and tables are extensively wed in clarifying points and concepts. Cansiderilble material is conveniently summarked in table form. The coverage of topics are far from being superficial, and frequent inclusion of current research topics makes the book relevent to the problems confronting modern biochemists. W I K T ~W. R NOWINSKI Important references are listed a t the end University of Tczas Medical Branch of each chapter. Galveston, Tezm 77660 While "Basic Biological Chemistry" may be very useful as a text in a substantial biochemical course, t,his reviewer seB a r k B i h g i c d Chemistry riously doubts if the book can successfully serve the objectives intended by the auHenry R. Mahler and Eugene H. Cordes. thor, namely, to provide an introduction Indiana University, Bloamingtau. Harto biological chemistry for "students lackper & Row, New York, 1968. x 527 ing comprehensive training in chemistry." pp. Figs. and tables. 18.5 X 26.5 em. Explanations given in such chapters as 2 $10.75. (Equilibria and Thermodynamics in Transformat.ions), 3 (Proteins: ClassificaAccording to the aut,harrspreface, this tion, Properties, Purification), 5 (Nucleic texthook was written primarily for st,,,dents who do not have sufficient training Acids) and 6 (Emyme Kinetics) are inadein chemistry to use the author's earlier quate for students who are not thoroughly book, "Biological Chemistry" (Harper & grounded in analytical, organic, and physical chemistry. The very extensive use Ilow). Even though there are brief exof chemical, biological, and biochemical cursions into t,hermodynamics, ditfmion terminology in the descriptive portions of rates, and kinetic theory, the main thrust the book makes the reading and compreof the book seems to be a qualitative dehension of these sections mast difficult for scription of the synthesis, properties and (Conlinurd on page AISB) metabolism of proteins, enzymes, carbo-
"Biochemist,ry and Morphogenesis," by Joseph Needham, and is almost exclusively dedicated to bacterial erowth. The chaw ter on membranes is t o t h e greatest extent devoted to bacterial membranes and only mentions cellular membranes in the multicellular organisms. The author failed t o correlate the chemistry of membranes with the living functions and practically did not discuss the role of membrane structure in permeability. In summary, as a textbook of biochemistry, Reithel's book is unsatisfactory; however, as a "chemist's view of biology" can be very useful.
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