NMR and EPR spectroscopy (The NMR-EPR Staff of Varian

NMR and EPR spectroscopy (The NMR-EPR Staff of Varian Associates). John R. Hollahan. J. Chem. Educ. , 1962, 39 (2), p A136. DOI: 10.1021/ed039pA136...
0 downloads 0 Views 1MB Size
BOOK REVIEWS considerable attention in recent years, receive hut a scant mention in Chapter 12. The book, intended for honors graduate students and research workers i n specialised fields, has been well pulled together by the editors so that i t reads as a connected text, while each chapter can stand alone as an authoritative treatise on one particular electrode type. The presentation of text and figures is pleasing throughout. On page 65, the ratio of the physical to chemical atomic =-eights should be amended to read 1.000276.

NMR and EPR Spectroscopy

The NMR-EPR Staff of Van'an Associates, Pslo Alto, California. Pergamon Press, Inc., New York, 1960. viii 288 pp. Figs. and tables. 16 X 23.5 cm. $12.

+

This volume is the product of the Third Annual Varian Workshop, held 1959, on nuclear and Octoher 19-23, electron paramagnetic resonance, and is a collection of papers presented by the staff of Varian Associates. One cannot resist commenting categorically that an over-dl attractive feature of the hook is its description of the present status of the equipment AND^^; J. D E B ~ T A U N E fields of NMR and EPR-the design, operating fundamentals, and apBoston College plications in physics and chemistry. Chestnut Hill,Mass.

The book is understandably terse in detailed development of resonsnee and electronic theory. Consequently, to the neophyte who is seeking mathematical and theoretical completeness, the material, though effectively concise, might appear somewhat abstruse. A general impression is that since the papers were each contributed rather independently, there is some repetition, and a t times an ineamplete precursory discussion is followed in a. later paper by a fuller development. The structure of the book is divided into three major areas: Introduction, High Resolution NMR Spectroscopy, and E P R Spectroscopy. Part I is an excellent qualitative and enlightening introductory commentary on thc physical principles of resonance, and why the NMR and E P R spectrometers are such ingenious devices for the detection of resonance. The dipolemagnetic field interaction, relaxation times, the chemical shift and coupling constants are equally well presented. As a matter of organization, there seem to he two maverick papers, the first (No. 18, P a r t 111) on Theory of E P R Spectra, which should more properly find itself in P a r t I, where the introductions are made, and No. 10, Analysis of High Resolution NMR Spectra, which should come near the beginning of Part 11. Part 11, containing ten papers, is devoted to high resolution S M R . Papers of special mention are NMR for the Physical Chemist, wherein a fairly detailed discussion is offered on the t,heory of fast, slow, and intermediate oxchange reactions of protons treated according to McConnell's method. Special techniques such as electric shims to improve field homogeneity, magnetic field modulation, and an NMR integrating system are each described in separate papers. Part I11 on E P R spectroscopy contains nine papers, only one of which deals specifically with the instrumentation of EPR. The remaining eight papers describe some very intriguing aspects of E P R application including biological and photochemical uses. One of the areas of E P R application in which much progress is yet to he made is that of color center systems. Once the atom, ion, or electron is locilliaed in a crystal, specific and reasonably long range interactmns between the electron or nucleus and lattice can arise which are extremely complicated to untangle. This problem is outlined in a paper entitled Paramagnetic Response of Color Centers. Other papers discuss theory of E P R spectra, paramagnetic ions in crystals, and dynamic polarization in liquids. The hook concludes with a. unique paper of four pages which discusses s. Color Center "Workshop" Experiment. This demonstration experiment involved several experimental vvariahles (temperature, microwave power level, and field modulation frequency and amplitude) and the principles of color center resonance. This book is recommended to anyone actively working in the field of NMR or EPR. It is also recommended to those seeking an idea of what is going on in the field currently-what some of the tech(Catinued on page A138)

A136 / Journd o f Chemical Education

nieal and theoretical problems are-although other texts will have to he eonsulted for a complete pirture.

University of Washington Seattle Gmelinr Handbuch der Anorganirchen Chemie, 8. Auflage, System Nummer 9, Sulfur, Part B

Edited by the Gmelin Institute under the direction of E. H. B. Pietseh. Verlag Chemie, GMBH, Weinheim, Bergstrasse, 1960. 1130 pp. Figs. and tables. 17.5 X 25.5 a n . 5173.50. This section of the eighth edition of Gmelin's handbook contains detailed in-

questionable existence, to peroxadisulfuric acid and those acids in which one or more of t h e oxygen8 is replaced by s. sulfur atom. Some idea of the nature of the material included may be gained hy the following subheadings under "Dithionous Acid": Formation. Preparation, i\Lodes of formation of the ion, Existence of free acid, Thermodynamic data. of formation; Physical Prope&x. Color, Light ahsorption, Raman spectrum, Magnetic susceptibility; Eled7oehemical Behavior. Conductance, Ionic rnobilitv. Potentials, Polamgraphic beha&; Chemical ReaUions. Acidity, Activity coefficient, Constitution, Molecule, Salt formation, Reactions with heavy metals, Thermal decomposition, Photochemical decomposition, Oxidation, with sulfur compounds and other reagents. Much of the data on the compounds is more inclusive, giving structure, moleculsr dimensions, probable composition in solution, etc. The index contains German and English headings. The instructions for the use of the Gmelin system are given in both languages. Theliteratureis reviewed up to 1949 and to 1960 for important compounds. The references are given with each subheading rather than compiled a t the end of the section. The user should carefully note the dates of the references and be guided as to the value of the data accordingly. Thus, the comparative strength of the acids is given as HCIO, > HBr > HCI > HNOs > H 8 0 4 on the basis of the moleculilr refraction (1928). The reicrenee to Getman "Outlines of Theoretical Chemistry" (1928) for further information is given a t the end of the page. The acidity function for HnSO*with references as late as Chem. Reu., 1957, is given on the next page. Since HOfor HCIO. and &SO4 are much more negative than those of HCI and HNOa, the order of acidities given on the previous page is open t o

(Continued on page A142)

A 138

/

Journd o f Chemical Education