NMR and chemistry; An introduction to modern NMR spectroscopy.

NMR and chemistry; An introduction to modern NMR spectroscopy.

SpectrochimicaActa, Vol. 50A, No, 5, pp. 1011-1013, 1994 Elsevier Science Ltd. Printed in Great Britain 0584-8539194 $6.00 + 0.00 Pergamon BOOK REVI...

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SpectrochimicaActa, Vol. 50A, No, 5, pp. 1011-1013, 1994 Elsevier Science Ltd. Printed in Great Britain 0584-8539194 $6.00 + 0.00

Pergamon

BOOK REVIEWS C H A R G E TRANSFER PHOTOCHEMISTRY OF COORDINATION COMPOUNDS by O. HORVATHand K. L. STEVENSON. VCH Publishers Inc., New York (1993), 380 pp. Price £98. Despite the recent substantial growth of interest in the photochemical properties of inorganic compounds, there has been no truly comprehensive review of the charge transfer photochemistry of coordination compounds for over 20 years. This book sets out to rectify the omission by reviewing that part of the scientific literature, appearing over the past 10-15 years, which relates to research on the photochemistry of coordination compounds of the p-, d- and f-block elements. The first three chapters of the book provide an overview of the theory of photochemistry while the larger part of the book presents a specialist review of the subject. In the first 32 pages the basic physics of light, photochemical processes, charge transfer and photochemical experiments is presented. This early section of the book may be largely unnecessary for photochemists and rather too brief for the novice seeking a text on photochemistry. However, it has the value of providing a useful introduction for the non-specialist needing the necessary theoretical knowledge to follow the photochemical literature without wishing to become an expert. In this way a self-contained volume has been produced which makes a specialised review more accessible to the non-specialist reader. The major section of the book contains a survey of the photochemical literature to the end of 1990. To keep the work as up to date as possible an appendix also cites over 50 publications from the 1991 literature. Being classed as organometallic rather than coordination compounds, metal carbonyl derivatives have been excluded from the review; although cyanide complexes arc included. In addition to work on d- and f-block elements, work on compounds of magnesium and many of the p-block elements is also described. The review of iron, ruthenium and osmium compounds, although at 60 pages the largest for any three elements, is rather more selective because of the large number of publications on these metals, particularly on ruthenium. The survey is arranged by element groups with chapters on {Cu, Ag, Au}; {Mg, Zn, Cd, Hg}; {AI, Ga, In, TI, Y, the lanthanides and actinides}; {Si, Ge, Sn, Pb, Ti}; {Sb, Bi, V, Nb, Ta}; {Te, Cr, Mo, W}; {Mn, Tc, Re}; {Fe, Ru, Os}; {Co, Rh, It}; and {Ni, Pd, Pt}. The style of presentation of the literature survey is more that of a specialist review than of a text book but a reasonably full account of the research is given considering that in total over 1700 literature citations are made, of which about one-third relate to the Fe/Ru/Os group. In addition to its organisation by element the book is indexed both by subjects and by compounds making it easy to locate information about particular metals or compound types. In this book, those preparing courses on the photochemistry of inorganic compounds will find a wealth of examples with which to illustrate their topic. The text represents a valuable contribution to the photochemical literature and will provide an important source of information for the specialist and non-specialist alike.

School of Chemistry The University of Birmingham Birmingham B15 2TT U.K.

C. J. JONES

NMR AND CHEMISTRY; AN INTRODUCTION TO MODERN NMR SPECTROSCOPY. Third edition. By J. W. AKrrr. Chapman & Hall (1992), 272 pp. Price £62.50. The book of Akitt is an introductory level text on theory and applications of nuclear magnetic resonance. Although the title of the book seems to imply purely chemical applications, biomedical NMR and imaging are treated as well. The 3rd edition comes almost a decade after the 2nd edition, which appeared in 1983. The first chapter treats the theory of nuclear magnetism and origin of the NMR signal. The magnetic properties of atomic nuclei are treated in some detail on a largely non-mathematical level. The second and the third chapters introduce nuclear shielding, the chemical shift, and J-coupling phenomena. The author gives information about chemical shifts of a variety of uncommon (from the NMR point of view) nuclei, which help the student to develop a feeling about how constitution and structure of a molecule affect the chemical shift, and what chemical shift ranges can be found. Isotope effects are discussed as well. Proton chemical shifts are treated in more detail and exercises are provided, but the discussion of carbon chemical shifts in structure elucidation is deferred to chapter 7 which covers multiple resonance and NOE. The author describes J-coupling involving nuclei with spin higher than ~ and provides examples from organometallic chemistry; such a treatment is uncommon but gives the student a more general and better understanding of coupling phenomena. The following chapter about relaxation completes the most basic theory of nuclear magnetism. The chapter that follows (chapter 5) treats some of the most important aspects of modern NMR, i.e. those of data collection, manipulation, and transformation from time to frequency domain. This chapter contains much information pertinent to modern FT spectroscopy, although quadrature detection occupies only four lines. In a marvellous chapter 6 chemical exchange is dealt with. This chapter is extremely valuable and includes some less common topics, such as high pressure NMR. In chapter 7, NOE and multipulse 1D experiments are introduced; as an extension of the discussion on how NOE and polarization transfer aid in accumulation of '3C data, exercises involving carbon spectra are provided. 1011

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Book Reviews

Chapter 8 introduces 2D spectroscopy. This is a new addition to the book, since the 2nd edition contained only a brief section about this, at that time, just-emerging field. This chapter illustrates the power of some common 2D techniques as structure elucidation tools; amygdalin, a gentiobioside of benzaldehyde cyanohydrin, is used as an example. Although the text gives the pulse sequences for the most typical experiments with some comments, the explanations of the theory are brief and difficult to follow, and are of little value. The book ends with chapters on biomedical NMR and on solid state NMR. The target group for the book stated in the 1st edition are undergraduate students, but the 3rd edition represents a fairly extensive text. The chapters on nuclear magnetism, chemical shifts, couplings and relaxation are very valuable and provide a good theoretical basis for a student, but exchanging systems, NMR imaging and solid state NMR arguably constitute advanced topics. Such an important area as 2D NMR is treated at a quite disappointing level--the title of the book and the 2D spectrum shown on the cover seem to promise more. A more careful discussion of the nature of the second dimension in NMR, and clear statements about what can and cannot be illustrated with the vector model would add greatly to the value of the book. The schematics of the NMR spectrometer given in the book show an iron magnet with a horizontal Bo field. As a consequence, illustrations of the coordinate systems for representation of magnetization vectors have a horizontal z axis. This is in contrast to what the student will encounter in all modern papers and books. Moreover, the book contains many reproductions of low-field CW spectra. Although they do provide adequate illustration of the points the author makes, this very extensive use of CW spectra, which look very differently from that which a student in a modern university is likely to encounter, and which have no connection to large parts of the NMR theory described in the book, is peculiar indeed. It is thus all too obvious that the original version of this book was written over 20 years ago. This is, however, also the strength of the book; carrying on good traditions from the previous editions, it contains a lot of valuable material not found in other, newer NMR texts. The truly multinuclear approach to NMR and many examples firmly related to chemical facts are the most important merits of this book.

Royal Danish School of Pharmacy Copenhagen Denmark

JERZY W. JAROSZEWSKI

SCANNING TUNNELING MICROSCOPY AND SPECTROSCOPY - THEORY, TECHNIQUES, AND APPLICATIONS (Edited by DAWN A. BONNELL). VCH Publishers (U.K.) Ltd. (1993), 436 pp. Price £80.00. ISBN 089573-768-X Almost 3000 publications dealing with scanning tunneling microscopy (STM), atomic force microscopy (AFM) and other planning probe microscopies (SPM) have appeared in the 10 years since the invention of STM by Binnig, Rohrer and Gerber and the seminal work which followed. Applications and developments continue to proliferate with the corresponding number of papers published increasing near exponentially. Indeed, a reasonable prediction for the current year would be ~ 1200 + new references. It is reasonable, therefore, to pose the question, "Where and how should the researcher new to the field approach the existing literature?" Or equally, "Where can one find out what STM and AFM (or their variants) offer that other microscopic techniques do not?" Details apart, such questions are of particular relevance, since the ready availability of robust, user-friendly SPM instrumentation, now means that non-specialists from diverse disciplines entering, or planning to enter, the field have to balance budgets against benefits. Were they first to consider STM and AFM techniques from their non-specialist perspectives all concerned could hardly do better than to start with this particular book. Anyone buying it for personal, research group, departmental or library use will find, as will colleagues, the money well spent. In style and presentation the book is eminently readable, both detailed and comprehensive in coverage. The editor and contributing authors are to be congratulated for their maintaining an evenness of quality throughout. However, before considering the book in more detail, one minor criticism is necessary. It is a pity that some of the more recent and novel applications using scanning probe technology for making localized (sometimes ultralocalized) measurements of almost any detectable property, i.e. thermal gradients, magnetic forces, photon emission and absorption, via local surface probes, are not considered in more significant detail. As to contents, these are organized in three parts dealing with, respectively, Fundamentals (four chapters), Structure of Sample and Tip Surfaces (two chapters) and Related Techniques and Applications (four chapters), followed by appendices which include a useful Fortran program for the numerical calculation of the tunnelling current. Thus, part I covers a brief Introduction (chapter 1), provides chapter 2 ( - 2 3 pp., Dawn A. Bonnell) dealing with Microscope Design and Operation, chapter 3 ( - 19 pp., J. Tersoff) on the Theory of Scanning Tunneling Microscopy and chapter 4 ( - 52 pp., R. J. Hamers) which gives a particularly useful detailed account of the spectroscopic variants of STM. In turn, part II deals with the Surface Structure of Crystalline Solids in chapter 5 ( - 47 pp., W. Unertl), followed by chapter 6 ( - 32 pp., G. Rohrer) on the important questions associated with the Preparation of Tip and Sample Surfaces for STM Experiments. Part III addresses Force Microscopy in chapter 7 ( - 58 pp., N. A. Burnham and R. J. Colton), BEEM and the Characterization of Buried Interfaces in chapter 8 ( ~ 3 5 pp., W. J. Kaiser, C. D. Bell, M. H. Hecht and L. C. Davis), Applications in Electrochemistry in chapter 9 ( - 4 6 pp., A. J. Bard and Fu-ren F. Fan) and Biological Applications of Scanning Probe Microscopy in chapter 10 ( ~ 7 3 pp., S. M. Lindsay). The last chapter provides, as well as a variety of applicational information about STM in a biological context, lucid consideration of the interaction forces within biopolymers and between probe and substrate with and without solvent or adsorbed overlayer. Moreover, the origins of STM contrast and biopolymer conductivity (important and unresolved problems) are likewise discussed in some detail. Chapter 9 elaborates the essential background and outstanding potential of