Annual Reports on NMR Spectroscopy: Appli-cations of NMR to

Jun 3, 2003 - Academic Press: San Diego, London. 2001. x + 146 pp. $124.95. ISBN 0-12-505344-4. Ian D. Gay. Simon Fraser University. J. Am. Chem...
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Progress in Inorganic Chemistry, Volume 51. Edited by Kenneth Karlin (Johns Hopkins University). John Wiley & Sons, Inc.: Hoboken. 2003. viii + 640 pp. $150.00. ISBN 0-471-26534-9. A recent book titled Chemistry for the Twenty-first Century raised the question (Earley, J. E. Review of Chemistry for the 21st Century; Keinan, E., Schechter, I., Eds.; Wiley-VCH: Gmbh, Weinhiem, 2001. J. Chem. Educ. 2002, 79, 33) of whether the main emphasis of chemical science in the next century will be “analytic” (rationalizing complex observed phenomena in terms of simple units) or “synthetic” (generating interesting behavior through new combinations). Volume 51 of Progress in Inorganic Chemistry indicates that both approaches are now important, but also suggests (at least to me) that today’s inorganic chemistry has a dominant interest in constructing new and interesting materials, rather than in simplifying complicated systems to find problems that can be solved analytically by theory. The volume contains five chapters. The first and last each have sufficient substance to have been published as monographs. The opening piece is a masterful review of the chemistry of lead(II) (including historical, environmental, and biological aspects) by Claudio, Goldwin, and Magyar. This article should be required reading for teachers of general chemistry, and for instructors of inorganic chemistry at any level. It is sometimes said that half of current medical knowledge is wrong, but nobody knows which half that is. One aspect of Pb(II) chemistry that many teachers think they understand is the “inert pair effect” that is held to govern redox and stereochemical behavior of plumbous species. This review shows the danger of a little learning. The unshared pair of electrons on Pb(II) may or may not be stereochemically active, depending on what other ligands are in the complex. The thorough discussion of the relativistic origin, varied importance, and limitations of applicability of this often taught (but widely misunderstood) effect, as well as the outstanding account in the same chapter of the important environmental impacts of lead, are highlights of this volume. Another chapter covers toxicological and nutritional aspects of the chemistry of chromium(III). In view of the medically important, chemically complicated, and perennially controversial nature of the action of chromium in biological systems, this review sets out to fill an important need. The long-term significance of this review will be decided by those currently active in the field. The authors indicate that almost everyone now recognizes that simple substitution reactions of Cr(III) in aqueous media are slow. However, I was struck by the absence of discussion of the many ways by which chromium(III) complexes can quite rapidly change their first coordination spheres by processes that are not “simple substitution”, including redox catalysis and rapid rotation of coordinated carboxylate groups. Perhaps the second article may indirectly suggest (as the first one explicitly pointed out) that a major fraction of what “everybody knows” may turn out not to be the case. 10.1021/ja025362g CCC: $25.00 © 2003 American Chemical Society

The remaining three chapters on aza-cryptands, sol-gel materials, and vanadium phosphates are more tightly focused than are the first two. The potential for wide general significance that was apparent in the first two reviews is not so evident in the latter three. However, more modest goals seem to permit more intensive, perhaps even exhaustive, coverage. In each of these three chapters, there is a clear emphasis on synthesis (both by design and by chance) of new and complicated materials, which may have interesting, and even important, characteristics. Few now remember that inorganic chemistry once had a “Renaissance”. This name for a burst of research activity in this field that began shortly after World War II suggests that inorganic chemistry had just previously been in a less than vigorous condition. Each of the papers in this outstanding volume clearly shows in quite diverse ways that inorganic chemical research is now active, varied, and vital. This excellent collection of reviews indicates that no second Renaissance is now needed. Joseph E. Earley, Sr., Georgetown UniVersity JA025362G 10.1021/ja025362g

Annual Reports on NMR Spectroscopy: Applications of NMR to Materials Science. Volume 44. Edited by G. A. Webb (University of Surrey) and I. Ando (Tokyo Institute of Technology). Academic Press: San Diego, London. 2001. x + 146 pp. $124.95. ISBN 0-12-505344-4. This volume, like others in the series, contains a collection of monographs on topics in nuclear magnetic resonance spectroscopy. The present volume contains three articles: “Applications of NMR Spectroscopy to the Structure and Ionic Aggregates of Ionomers” by Yoshimizu and Tsujita, “Applications of NMR Techniques to Coal Science” by Saito, Kanehashi, and Komaki, and “NMR Studies of Strongly Correlated Superconductors” by Asayama, Kitaoka, Zheng, Ishida, and Tokunaga. The articles appear to be up-to-date at time of publication and include references up to the year 2000. They are generally wellwritten and display a high standard of English. The first review deals with ionomers: polymers that contain ionizable pendant groups, such as carboxyls or amines. These substances react with acids or bases, yielding ionic groups throughout the polymer. The conformations and mechanical properties of polymers are strongly dependent on the degree of ionization. The present review covers NMR studies, largely in the authors’ laboratories, of acidic ionomers, mainly ethylenemethacrylic acid copolymers, and the “salts” produced by their neutralization. Studies of Na and Zn salts are emphasized. Some general introduction is provided, with a summary of the results of non-NMR studies. Using NMR spectroscopy, crystallinity J. AM. CHEM. SOC. 2003, 125, 9237-9238

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is assessed from splitting of the backbone -CH2- lines in 13C CP/MAS spectra, and motional information is inferred from 13C relaxation data. Some information is also presented on 23Na and 113Cd NMR spectroscopy of ionomers that have been neutralized by the corresponding bases. The authors briefly describe blends of ionomers with other polymers. The second article deals with NMR studies of coals. The first part of the article reviews the older literature on 1H and 13C spectroscopy of whole coals. These studies have generally been disappointing, because the chemical complexity of coal overwhelms the resolution achievable in solid-state NMR spectroscopy. This is followed by sections devoted to 15N NMR studies to determine the character of nitrogenous coal components and to 35Cl and 27Al NMR studies of coals. These latter studies might perhaps be of some use in characterizing the nonorganic components of coals. NMR imaging studies of coal samples, performed mostly in the authors’ laboratories, are described in the final section of this article. These experiments mainly image the mobile proton population of the coal, and a series of T1-selective images are shown. Finally, the authors describe construction of a probe that permits NMR imaging at temperatures up to 600 °C. A fascinating series of images is presented, displaying the evolution of mobility as a function of temperature, and the importance

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of these studies in the understanding of the coking process is discussed. Saito et al. describe NMR studies of superconductors, particularly heavy fermion superconductors such as CeCu2Si2, and the high temperature cuprate superconductors in the final chapter of the volume. Considerable experimental data, derived mainly from studies in the authors’ laboratories, are presented and are comprised mostly of T1 and Knight shift data for a wide variety of nuclei such as 63Cu, 9Be, 195Pt, 27Al, 17O, and 105Pd in many superconductors. These measurements are reported as a function of temperature, in most cases down to 0.1 K, or below. Some NQR data are also reported. Unfortunately, the discussion of these results assumes a knowledge of superconductivity at a level unlikely to be possessed by most readers of a general NMR spectroscopy journal. There is neither an introduction to the theory of these types of superconductors nor is a reference given to such an introduction. Accordingly, the results will probably be of interest to specialists in superconductivity, but are unlikely to have much impact on a broader readership. Ian D. Gay, Simon Fraser UniVersity JA0253181 10.1021/ja0253181