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Book Review Principles of Electron Spin Resonance. (Physical Chemistry Series.) By N. M. Atherton

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BOOKS
Mature Methods
Chemistry of Non-Stoichiometric
Compounds. By K. Kosuge. Oxford
University Press, Oxford, 1994.
262 pp., hardcover E 55.00.-ISBN 019-855555-5
In this monograph Koji Kosuge, Professor of Solid-state Chemistry at Kyoto
University, reviews a subject that is of
fundamental importance to chemistry, It
is only through understanding theinternal
processes of solid materials, i.e. the nature
and behavior of the relevant particles or
chemical stimuli, that one can apply
chemistry to solids in analogy to the successes of the acid-base or redox concepts
of “wet chemistry”. The appearance of a
book on this subject is therefore to be welcomed. Regrettably, however, it does not
succeed very well in its aims.
The choice of topics seems promising at
first. The starting point is the thermodynamics of mixtures, which is then applied
to the equilibrium of defects, first in dilute
systems, then in more concentrated systems. and finally in those that deviate
greatly from the concentration of the ordered phase. However, there is no treatment of chemical diffusion. (In this book
the term “diffusion coefficient” is used
only in the sense of a tracer diffusion
coefficient.) The last chapter can be recommended. dealing with extended defects, shear structures, Vernier structures,
micro-twin structures, intergrowth structures, and adaptive structures, and containing a wealth of information that is
chiefly useful to the chemist interested in
crystallography. Unfortunately high-temperature superconductors. which would
have nicely completed this chapter, are
not covered.
The first of the three chapters, making
up at least half the book, cannot be recThis scction contains book reviews and a list of
new hooks received hy theeditor. Book reviews are
written by invit;ition from the editor. Suggestions
for books to be reviewed and for book reviewers
are welcome. Publishers should send brochures o r
(better) books to Dr. Ralf Baumann. Redaktion
Angewandte Chemie. Postfach 1011 61. D-69451
Weinhein]. Federal Republic ofGermany. The editor reserves the right of selecting which books will
be reviewed. Uninvited books not chosen for
revie% will not bc returned.
ommended. There are numerous inaccuracies and errors which will spoil the pleasure of reading the book. A few examples
follow.
The nomenclature is not in accordance
with conventions in the literature. Moreover, there is confusion between absolute
and relative charges. and worse still, the
symbols for these are confused. On page 45
the regular electronic state is denoted by
“eh”, whereas on page 85 it is correctly
identified by the symbol “0” in the building elements notation. In the case of ionic
equilibria a mixture of structure elements
and building elements is used. The introduction to chemical equilibria and the
configurational enthalpy (Ch. 1.2) is
clumsy and often inaccurate. One could
perhaps tolerate the frequent switching
between differences and differentials. but
not the identification of -(AGo-AG)/RT
as an equilibrium constant. In the discussion of the formation of defects (p. 18)
there is no mention of the vibrational entropy, which has an important influence
on the free enthalpy of formation, especially in high-temperature chemistry. The
fact that the temperature dependence of
the equilibrium constant for the bandband transition is determined by the band
gap is explained by the following curious
statement: “The rate of ionization is believed to be roughly equal to that of the
dissociation of water . . . and therefore we
put [eh] = 1 .” (?).This is just a small selection. The most annoying aspect of the
errors is that they destroy the reader’s
faith in those parts of the text that are
properly written.
Joachim Maier
Max-Planck-Institut
fur Festkorperforschung
Stuttgart (FRG)
Principles of Electron Spin Resonance. (Physical Chemistry Series.)
By N . M . Arherton. Ellis H o r w o o d ,
Chichester, 1994. 585 pp., hardcover
$ 127.00.-ISBN
0-1 3-721762-5
This book is a revised and updated version of ESR--Theory and Applications
which appeared in 1973, and the change in
the title reflects the author’s aim of placing greater emphasis on the fundamentals
of ESR spectroscopy. Rapid changes are
currently occurring in the experimental
methods used in ESR spectroscopy,
summed up by the key phrase “pulsed
ESR spectroscopy”, opening up entirely
new possibilities in time-resolved and
multidimensional measurements. In turning back to basic principles at this time the
author is tapping a great potential but also running some risks.
As is to be expected for a method that
has reached maturity, the literature contains a wide variety of notations for the
treatment of special cases, making it difficult for students and users to relate the
techniques to their specific problems by
analogy with methods that are already familiar. Here we undoubtedly find one of
the strengths of the book. as the author
consistently treats spectral calculations
and relaxation processes at a level suitable
for the average reader. He also helpfully
“translates” even very recently published
papers, so that the reader who works consistently through the book gains a comprehensive insight into topical problems.
However, the discussion of the possibilities opened up by pulsed ESR spectroscopy is less successful. Only 80 pages
are devoted to recently developed methods such as pulsed ENDOR, 2 D ESR
spectroscopy, and optical spin polarization, and these are treated essentially at an
introductory level, in contrast to the first
ten chapters (440 pp.) which deal with
continuous-wave (CW) forms of ESR and
ENDOR spectroscopy, explaining their
capabilities and describing many examples of a nontrivial kind.
A work that has the word “principles”
in its title invites comparison with other
books that make similar claims. Examples
are: Principles of Magnetic Resonance in
One and Two Dimensions (Ernst. Bodenhausen and Wokaun), Principks of Magnetic Resonance (Slichter), Principles of
Nuclear Magnetism (Abragam). and EPR
of Transition Ions (Abragam and Bleaney),
all of which undoubtedly have the character of handbooks. In my view the
present book is instead more accurately
described as a “comprehensive introduction”, although this classification in no
BOOKS
way detracts
from its value and useful-
ness.
Against the background of constantly
shrinking library budgets, one must look
a\ a n y new book and ask whether its
purchase is really essential. Here the needs
of the specialists are less important than
those of the advanced students who, in the
course of their work, need to find quick
solutions to practical problems without
first having to make a deep and detailed
study of the methods. This book offers a
very good foundation for that purpose. It
has the advantages of a detailed subject
index and an up-to-date bibliography (although it is difficult to understand why, in
the age of computer-aided text processing,
all the umlauts have been consistently
omitted from names such as Schrodinger,
Hiickel, and Mobius). To sum up, the
book fulfills its aim of providing students
and scientists whose main field is physical
chemistry with an up-to-date and comprehensive basis for understanding ESR
spectroscopy.
Klaus-Peter Dinse
Institut fur Physikalische Chemie
der Technischen Hochschule Darmstadt
(FRG)
Computer Simulations of Biomolecular
Systems. Theoretical and Experimental
Applications. Vol. 2. Edited by PK E
vun Gunsteren, P. K. Weinev and A . J;
Wilkinson. ESCOM, Leiden (Netherlands), 1993, 589 pp., hardcover HFI
41 5.00.-ISBN 90-72199-15-4
About 18 years ago when J. A. McCammon, B. R. Gelin, and M. Karplus published the first molecular dynamics simulation of a protein (Nature 1977, 267,
5 8 5 ) , the accepted picture of a biological
molecule was essentially that of a rigid
body. The molecular structures of several
proteins and of DNA had already been
successfully determined by X-ray crystallography, and the results were represented
by a rigid wire model. The dynamic aspects
that play an important role in all biological processes could not, and still cannot.
be directly observed experimentally, at
least down to atomic-scale resolution.
When the results of molecular dynamics
calculations first began to appear, it became possible to follow the molecular
motions as if in a cine film. These calculations were restricted to relatively small
molecules, and the time intervals that
could be simulated were very short, in the
order of picoseconds. However, such simulations made an important contribution
to revising the ideas based on the rigid
wire model.
The book reviewed here shows how simulation methods have developed during the
last 28 years and reflects the present-day
importance of the subject. In 25 chapters,
introduced in a very detailed preface by
Martin Karplus. various authors review
simulation techniques, force fields. and
applications. The contents list alone occupies more space than is available for this
review, and it will only be possible here to
pick out some of the topics covered.
The first two sections of the book are
concerned with fundamentals, namely simulation techniques (algorithms for molecular dynamics and Monte Carlo calculations) and force fields. A force field should
on the one hand approximate as closely as
possible to the real quantum-mechanical
situation, while on the other hand allowing rapid and efficient calculations. Because of the need to keep the computing
time within reasonable bounds, compromises are always necessary. Simplified
force fields are necessary in order to study
slow processes such as protein folding.
However, even more detailed force fields
are still only approximations, and it is important for the user to know how this can
affect the results of the calculations.
One of the most important applications
of molecular dynamics simulations is the
calculation of free energies. The book offers an excellent introduction to this topic,
with particular emphasis on possible difficulties and sources of error. Several examples of successful free energy calculations are given. On the other hand it is also
clearly explained why the predictions from
the calculations may not always be correct.
The three chapters on the use of molecular dynamics calculations in refining
molecular structural data from X-ray
crystallography and N M R spectroscopy
can be regarded to some extent as occupying a special position in the book. Here
one is using the molecular dynamics algorithm not to investigate the dynamics of
a molecule but as an optimization method
for the solution of a difficult nonlinear
problem. The excellent convergence properties of the molecular dynamics method
have revolutionized the process of structure refinement. The occasions when individual steps must be performed laboriously by hand are now increasingly rare, and
the end result, the refined structure, is
reached much more quickly than in the
past. However, the close connection that
exists between molecular dynamics and
N M R spectroscopy especially is also mentioned here.
I learned much from reading this book,
and it can be recommended as a thorough
introduction to the simulation of macromolecules. It is a valuable source of practical information and an indispensable
work of reference. In a multiauthor work
such as this some degree of non-uniformity is perhaps unavoidable, as also is a certain amount of overlapping in chapters on
related topics. However, I regard the latter as an advantage, since it means that
important topics are seen from different
points of view. All the aspects of the simulation of macromolecules discussed in the
book are active areas of research, and as is
made clear in the preface many questions
still remain to be finally answered, even
with regard to the methods. It is pleasing
that many of the authors are able to view
their own work critically from a distance.
It is very useful, especially for a newcomer
to the field, to be made aware of problems
in the application of these methods.
Michael Nilges
European Molecular Biology Laboratory
Heidelberg (FRG)
Ideas in Chemistry. A History of the
Science. By D. Knight. Athlone Press,
London, 1992. 21 3 pp., hardcover
E 38.00.-ISBN 0-485-11390-2
What a splendid title! It promises a
much needed book on the intellectual content of chemistry, and on its trade: by insemination, as with “reaction”, borrowed
in part from the actionlreaction pair in
physics; by dissemination, as with “affinity” or “catalysis,” terms and concepts that
have entered common language too; or as
with “complementarity”, which spawned
molecular biology.
Is it because of the inheritance from
alchemy? Chemistry is a conceptual science, rooted in material operations. Other
sciences (astronomy, biology, o r physics)
do not transform their subject matter as a
matter of course. But chemistry intellectualizes its metamorphoses, to an extent that
is astounding, given the huge distance from
the macroscopic to the microscopic that it
entails: to think and to talk of molecular
objects, reaction paths, molecular orbitals,
atomic hardness, etc. demands temerity
and insight.
What is needed is a thesaurus of key
chemical notions. There are two o r three
dozen central concepts, such as acidity or
coordination, plus a hundred or so more
peripheral but also necessary notions, such
as steric hindrance o r chain reaction.
Someone should provide such a compendium, with present-day definitions, capsule
histories, and illustrative quotations.
2SJJ
Atigrx .
CAern. In[. Ed. D i g / . 1995. 34. No. Y
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