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Book Review Transient Techniques in NMR of Solids. An Introduction to Theory and Practice. By B. C. Gerstein and C. R. Dybowski and C. R. Dybowski

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Inorganic High Pressure Chemistry. Kinetics and Mechanisms. Edited by R. van Eldik. Elsevier, Amsterdam
1986. x, 448 pp., bound, HFI 280.00.--ISBN 0-44442682-2
High pressure kinetics has become more and more important in the last years. Especially in coordination chemistry it brought new insights into the reaction mechanisms.
The editor Rudi van Eldik is one of the leading experts in
high pressure kinetics of coordination compounds. The
reader will notice his experience and competence. H e himself has written a large part of the book, thus making it
very coherent. There are almost no repetitions.
The introductory chapter by van Eldik describes the high
pressure techniques and methods of analysis comprehensively. The experimental results are arranged according t o
reaction types: Solvent Exchange Reactions (Y. Ducommun
and A . E. Merbach); Substitution, Isomerization and Related Reactions of Octahedral Complexes ( R . van Eldik)
and of Four-Coordinate Complexes ( M . Kotowski and R .
oan Eldik); Electron Transfer Reactions (T. W . Swaddle);
Photochemical and Photophysical Processes (I? C. Ford);
as well as Bioinorganic Systems ( K . Heremans). The final
chapter by van Eldik demonstrates how much the subject is
in a state of flux. Simple transition state theory is used to
discuss the high pressure data almost all over the book. It
is only in the last chapter that van Eldik shows what consequences the simplifications have and which extensions
were suggested. These difficulties become evident especially in high pressure photochemistry. Here, the application of transition state theory is not justified a priori. In the
introduction to his chapter Ford explicitly stressed this
point: “the processes subsequent to photoexcitation have
t o be treated somewhat differently”. However, he also uses
the simple transition state theory t o discuss the experimental results. Obviously there is nothing better.
I am sure this monograph will remain the standard work
on high pressure kinetics for years. Everyone working in
this field will use it and quote from it. The nonspecialist
might be discouraged by size and price. But there is hope,
its contents will get into text books on reaction kinetics
and thus will becomk widely known. For, the pressure dependence of rate constants will soon become as important
as the Arrhenius diagram is to-day.
Fritz Wasgestian [NB 829 IE]
Institut fur Anorganische Chemie
der Universitat Koln (FRG)
Stereoselective Synthesis. By Mihaly Nogradi. VCH Verlagsgesellschaft, Weinheim 1987. xiv, 356 pp., bound,
D M 168.00.-ISBN 3-527-26467-1
The area of stereoselective synthesis has been intensively
studied for a good decade, and has thus reached some degree of maturity. Therefore both outsiders and those working in the field have a n equal need for a critical review
which sets out the principles and highlights the reliable
methods. We already have, from the years 1983-1985, the
five volume work “Asymmetric Synthesis”, edited by J. D.
Morrison (see Angew. Chem. Int. Ed. Engl. 25 (1986) 848),
which describes the essence of the more important methods. What can the present book offer us?
The introduction, which discusses the basic concepts of
stereochemistry, shows the author to be a scientist who
proceeds in a systematic way. This is followed by chapters
on stereoselective catalytic hydrogenations, stereoselective
non-catalytic reductions, stereoselective oxidations and
Angew. Chem. In!. Ed. Engl. 26 (1987) No. I0
stereoselective C-C bond-forming reactions. Finally there
are two shorter chapters on stereoselective pericyclic reactions and stereoselective carbon-heteroatom bond formation. However, the critical evaluation which we had hoped
for constitutes only a small insignificant part of the book,
which being simply a collection of data is scarcely more
exciting to read than a telephone directory. The author
has, however, assembled, under types of reactions, all the
important factual information on stereoselective syntheses
from recent years, and a large amount of additional data.
Is this book then to be regarded as the “Beilstein” of stereoselective synthesis? The scandalously long time interval
between the end of literature coverage in 1984 and the
book’s publication in 1987 is reminiscent of that. But that
is the only resemblance- whereas Beilstein is recognized
for the proverbial reliability of the data, Nogradi’s book
contains many incorrect structural formulas. These, regrettably, include quite a number of errors which alter the
intended meaning. Worse still, some reactions which superficially look correct are in fact given wrongly, e.g. because the configuration of a stereogenic center in a product is shown wrongly, or the description of the reaction as
a whole does not correspond to that in the papers cited. Of
course, the reader only notices such errors in those topics
with which he is familiar. It is unfair, but understandable,
to draw conclusions from this about the treatment of other
topics. In short, viewed in this light the book is a source of
irritation.
Despite these criticisms I must give the author credit
where it is due. Behind this collection of data there lies a n
immense amount of work, and the book is certainly of
value insofar as it contains a wealth of well organized data
on stereoselective syntheses. This includes much factual
information and examples which the reader interested in
this field could not otherwise readily find. Nevertheless, all
users of the book are strongly advised to check the data by
consulting the original papers!
It may occur to the reader of this review that minor defects of presentation and inaccuracies, which one would
usually criticize, have not been mentioned here. Such
faults pale into insignificance compared with the lack of
care in presenting structural information. It is perhaps typical of the book that the page devoted to advertising by
VCH Verlagsgesellschaft shows a n sp2 hybridized carbon
atom with tetrahedral bond angles!
Reinhard W . Hoffmann [NB 838 IE]
Fachbereich Chemie
der Universitat Marburg (FRG)
Transient Techniques in NMR of Solids. An Introduction to
Theory and Practice. By B. C. Gerstein and C. R. Dybowski. Academic Press, New York 1985, xi, 295 pp.,
bound, $59.00.--ISBN 0-12-281 180-1
As the authors state this book is written for students
working in the field of high resolution N M R spectroscopy
of solids, who wish to gain a thorough understanding of
this specialized topic. They have sought to convey to the
reader their own, quite individual view of this subject, the
fascination which it generates, and their own pleasure in
the scientific concepts involved. To this end they use a very
lively style of language rich in individual idioms and expressions. They treat at length with very detailed calculations the fundamental topics, including some rather trivial
ones. Time and again the authors feel obliged to lead the
reader into digressions, e.g., into complex numbers, alter1053
nating current circuits, selected topics in magnetostatics,
some of the fundamentals of quantum mechanics and linear algebra, and into the mathematics of exponential operators.
However, accuracy sometimes becomes lost in the authors’ enthusiasm for the subject. Thus, for example, they
talk about “decoupling of differential equations,” where
what they actually mean are linear first-order differential
equations. A more bizarre example is seen on p. 21, where
the symbol t is used with two different meanings within
the same simple equation. The misprint demon has struck
in a particularly malicious way on p. 167, where, as a result
of a “0” (zero) having been converted into the letter “0”,
the whole thing has turned into a hopeless mess.
In a sense the impression is conveyed that the book has
been compiled in such a way as to make it superfluous for
a student working on solid state NMR spectroscopy to
study any other text. The essential problem of the book is,
though, that it is addressed to a fictitious readership.
At the beginning of Chapter 5, on p. 198 (of a total of
275 pages), the authors state that all that has gone previously is only a preparation for the real objective, which is
to understand the mechanism of multipulse cycles. I am
sorry to have to say, though, that the heyday of multipulse
cycles took place ten years ago. Throughout the world
there are now only a few groups working in this particular
field and their number is decreasing rather than growing.
Gerstein and Dybowski mainly ignore the successes of the
multipulse technique, which in my view are best seen in
single crystal studies. It thus seems an ironic accident that
in the one example relating to single crystal measurements,
data containing systematic errors are used. It is casually
stated that in any case most samples are in the form of
powders. The hope is expressed that a combination of
multipulse cycles with rapid rotation of the sample about
the “magic angle” (here dealt with only briefly) will yield a
method equivalent in information content and ease of interpretation to true high resolution liquid state NMR spectroscopy, which is so outstandingly successful as an analytical technique. However, one hardly finds in this volume
any convincing example to support such a hope.
The final chapter is devoted to heteronuclear pulse experiments. The style here is different. We no longer have
detailed analyses and a complete understanding, but instead a more or less traditional presentation of well-known
techniques. It is clearly apparent that the authors are here
no longer drawing on their own store of experience and
knowledge to the extent that they are in the earlier chapters.
The literature citations are a peculiar feature of the
book. On the grounds that this is a textbook, Gerstein and
Dybowski avoid citing original papers so far as possible. In
some places, however, original work is deliberately cited.
The reader may easily guess at the system which is used.
Writing a whole chapter on multipulse cycles and homonuclear pulse experiments in solids without mentioning the
name of J . S . Waugh even once in the text, is, to say the
least, a strange thing-and this is by no means an isolated
example.
Research libraries concerned about full coverage will
not be able to avoid buying this book, but I fear that there
will not be many students, at least in Germany who will
give themselves the “pleasure” of studying it systernatically.
U . Hueberlen [NB 801 IE]
Max-Planck-Institut fur medizinische Forschung,
Heidelberg (FRG)
1054
Low Energy Electrons and Surface Chemistry. By G. Ertl
and J. Kiippers. VCH Verlagsgesellschaft, Weinheim
1986. XII, 374 pp., hard cover, DM 168.00.--ISBN 3527-26056-0
If Irving Langmuir were to appear again on the scene in
surface science he would be captivated by many things, not
the least important of which is the ability we now have of
being able to probe the composition and structure of solid
surfaces with great dexterity and precision. To test the theory of monolayer saturation in adsorption, proposed by
Langmuir, it was necessary to use high-area solids, typically activated charcoal or silica gel which have areas ranging from 20 to 400 m2 g-’. Only by boosting the extent of
the adsorbed phase in this way was it possible to cope experimentally with the reliable measurement of adsorption
from the gas phase or solution. Nowadays, however, it is
routinely possible to monitor the build-up of monolayer
volumes, Vm, from fractions of coverage of 1 0 - ~to unity
when the surface area is no more than a few cmz g - ‘ . The
principal cause of the revolutionary advance has been the
use of electron, and other beams (including soft X-rays,
and ions of light elements) as primary probes for arriving
at the composition, stoichiometry and structure of two dimensional ordered o r disordered two-dimensional structures at solid surfaces. Low-energy monoenergetic electrons (1 to 5 ev) beams are ideal for exciting the vibrations
of chemisorbed and physically adsorbed layers; and from
the diffraction of monoenergetic electrons of energy in the
range 60 to 300 eV, a great deal can be inferred about the
atomic disposition of the exterior surface of a bulk solid
and of overlayers that can form upon it.
It would be difficult to overemphasize the importance of
the study of such systems: they are deeply implicated in
the phenomenology of catalysis, corrosion, epitaxy, and
the vast ramifying technologies that hinge upon these including the fashioning of new devices from quantum well
lasers to fast transistors. At the fundamental level, too, a
great deal needs to be learned about the basics of surface
science. Why does the sticking coefficient of a given gaseous species vary so enormously from one crystal face to
another on a simple solid such as tungsten. For graphite,
for example, the ‘anisotropy’ in sticking coefficient of oxygen as between the prismatic and basal faces is a factor of
some 10”.
In the last two decades major progress has been accomplished in enlarging our understanding and control of the
properties of surfaces. There have been dramatic improvements ever since the first edition of this very fine monograph appeared in 1974. The reader is given concise, expert guidance in numerous facets of surface science, and,
in particular, is introduced to all the principal ways in
which the strong interaction of electrons with matter are
turned to good advantage in gaining further insights into
surface properties and behavior. Only a fastidious concern
for perfection leads one to discover minor almost trivial,
faults with this book. The reviewer is a little disappointed
(and perhaps a few students who will read this text avidly,
will be too) that a more specific definition of work function (introduced on page 101) is not spelled out. The work
function is a notion that often causes confusion for those
that encounter the surface properties of solids for the first
time. A minor omission is a detailed discussion of lowresolution, high-energy electron energy loss spectroscopy
which is currently finding increasing relevance as a tool in
the science of catalysts. But this is understandable if the
title is to be interpreted literally.
The book is lavishly illustrated with the important points
Angew. Chem. Int
Ed Engl. 26 (1987) No. I0
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