Lecture notes in chemistry, volume 9. Crystals as giant molecules

chelnistry of smnll mdecules. Fitzgerald B. Bramwell. Brwklyn College. Brwklyn. NY 11210. Lecture Notes In Chemistry, Volume 9. Crystals as Glant Mole...
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and its derivatives. There is a useful tabulation of PES data for 100 small rine comnounds which is similar in format to the table prehensive coverage of the literature. Each monograph tends to stress representative examples and refen the reader to more specialized reference material. The writing is crisp, well edited, and presents a variety of viewpoints on the interpretation of such spectra. However, only the third and fourth monographs, (which have the same author in common), show continuity in style, content, and level of presentation. This text is desiened to serve as a reference -guide for ad" vancrd spectruac ilpir relearch on the photuchelnistry of smnll mdecules. Fitzgerald B. Bramwell Brwklyn College Brwklyn. NY 11210

Lecture Notes In Chemistry, Volume 9. Crystals as Glant Molecules. A. JulQ, Springer-Verlag. New Yo*, NY, 1978. vii 135 pp. 16.5 X 24 cm. PB $10.50.

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The series "Lecture Notes in Chemistry" of which "Crystals As Giant Molecules" is a part aims a t quick, informal, high level reports of new developments in chemical research and teaching. Such volumes have a potential for being useful to both teachers and students and it is this which the oresent revlew attrmptc to assecs. In this hook. Julg covers material on crystals from a point of view which is h t h different trom and more extrnrively worked out than that usually found in advanced tertIrmku. His overall theme i* that mderular orbital theory provides a useful framework for understanding phenomena associated with crystals just as it does for individual molecules. In developing this framework he makes extensive use of the concept of hybridization. For example he discusses sodium chloride in terms of a cell consisting of one sodium atom and six chlorine atoms with the eight valence electrons contained in four delocalized orbitals constructed from the s and p orbitals of the chlorine atoms and spSd2 hybrids of the sodium. Net charges on Naand C1 turn out to be close to those of the isolated ions. The overall stability of the structure is related to the change in the energy of the isolated cell arising from the proximity of other cells. There are six chaoten. The first reviews mdrc ular orhital theory, including localimd and nonlocalired hmdiny, and hybridized ort,itals fnm aimple rp to rp 'dsf I. Chapter ~

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I1 aoolies .. these considerations to molecular and marnmolerular crystal*, with the relatlon between hyhrid17atiun and structure discussed where pertinent. This material is useful and much of it is comprehensible without a study of Chapter I. The chapter ends with a discussion of cohesive energies. Chanter I11 deals with "Electron Charees and Ionirity in Macromolecular Crystals." Chapter lV, "The Crystal Arrangrmrnt." first discusses the inadequacies of the ratio of ionic radii as an index of crystal structure and then shows how qualitative considerations derived from examination of hybridized orbitals and from simple molecular orbital theory can provide useful insights into many systems. Finally there are two short chapters on "Distortions Caused by the Existence of Faces and the Finite Sizes of Crystals," and "External Shapes of Crystals." This bwk would have been much more useful to the uninitiated in the subject if it had been edited more carefully. Misprints, awkward choices of English words, phrases that do not make sense, and failures to define wnbols, lessen its utility. There are several potentially confusing choices of poor English equivalents to the French. For example, ''Repartition" becomes "repartition" instead of the commonly used "distribution"in discussing electron density; "quadratique" hecomes "quadratic" rather than "tetragonel" with reference to crystal structure; "faible" is consistently rendered as "weak when ''small" is more appropriate. As one of several examples of nonsensical phrasing consider the following from p. 99: ". . . ,na (denotes) the number of atoms situated on a face, but neither on a corner nor on a face.. . ."One of a series of failures to define symbols occurs an p. 66 where the symbol "A" is introduced without definition just after having been used to denote the Madelung constant on the previous page, the symbol r is not defined, nor are the symbols used for ionization potential and electron affinitv. I n theend, thrse flaws are more annoylng than d~sabhng,and so the book can be rec ommended to teachersot phys~caland mor ganic chemistry who are interested in e m ples of the application to crystals of the same quantum chemical concepts which they use in describing molecules. Students who have some background in quantum chemistry, including elementary molecular orbital thwry, and some knowledge of the solid state might also benefit from it. Colin MacKay Haverford College Haverford. PA 19041

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Flames-Their Structure, Radlatlon and Temperature, Fourth Edltlon A. G. Gaydon and H. G. Wolfham: C h a p man 8 Hall Ltd.. U.S. Distribution bv Methuen, New ~ o r k ;NY. 449 pp. ~igs..andtables. $49.95.

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Journal of Chemical Education

This is the fourth edition of the wellknown and respected book concerned with

the physical processes occurring in flames. The fourth edition contains the hulk of the material of the third, with the addition of pertinent material, text, diagrams and references, covering advances in the field from 1969 to 1918, with a few references to work done in 1979. The most thorough revisions relate to the sections of flame propagation, structure of turbulent flames and soot formation. The chapter entitled "The Structure of the Reaction Zone" contains the particularly valuable additions of (1) a detailed discussion of mechanisms of flame propagation in the HzlO~lNzand methanelair flames, with associated kinetic data --.-, (21 the concept of flame stretch,and 1.O the fnrmation of oxides of nitrugen. Ilnfonunawlv, there is noexplicit discussion or reference & work on how the pollution hazard.. NO..-. can be reduced in various combustion processes. A dircusrion of the pnhlrm of scot mluction in the environmrnt is similarly lacking. The application of the laser to the study of flames is described primarily in relation to laser-doppler anemometry (the measurement of localized gas velocities) and the measurement of rotational and vibrational temoeraturr prufiler of flnmw uvrng laser Haman spectroscupy and ('ARS The crmcal evaluation of all methods of temperature measurement, including new work on ionization and electron temperatures, is particularly helpful. To those who use the third edition as a stnndard reference, the fourth edition is highly recomnlended because of its wpalth uf new material, particularly the references. Tu those who are contemplating the purchase of a reference bwk, for personal or student use, again, the fourth edition is highly recommended. The clarity of presentation, the critical discussion of the measurement and nature of the physicd processes occurring in premixed and diffusion type stationary flames, and the large number of references to the original literature, all recommend this book to those venturing into the complex world of flames. Richard A. Ashby The N.S.W. lnstitufe of Technology, P.O. Box 123. Broadway. ~

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N.S.W. 2007

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Glassblowing: An Introduction to Artistic and Scientific Flameworkino. ", Fourth Edltlon Edward Carbeny, M G L S Publishing. Marshall, MN, 1980. Figs. and tables. 262 pp. 21 X 25.5 cm. $16.95. "Glassblowing," by Edward Carherry, was written as a textbwk for a one-quarter or (Continuedon pags A284