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Book Review Pulsed Magnetic Resonance NMR ESR and Optics. A Recognition of E. L. Hahn. Edited by D. M. S

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of-the-art, is there any merit in a detailed treatment of methods that are now largely of historical interest?
The first thing that strikes one about this book is its enormous size. The book is over 21/2 inches (6.4 cm) thick, weighs
over 5 % pounds (2.6 kilos), and contains 1500 pages. The
text has been reproduced from camera-ready copy that is not
justified oil the right. Many pages are only partially filled
and diagrams typically take up a whole page. It is my impression that this book represents a monumental waste of paper,
for the entire contents could have been contained in a work
of less than half the present length if the book had been
typeset in the conventional way. The text may be roughly
divided up into three sections each of some 500pages in
length. The first third concerns itself with a description of
methods used for predicting the properties of pure organic
compounds, the middle third discusses the characterization
of molecular structure by means of various molecular descriptors. and the final third lists all of the literature references cited in the book and also includes ten appendixes.
Roughly speaking, the first 500 pages are devoted to discussion of now dated methods (such as additivity methods), the
next 500 pages make brief mention of more modern methods
(such as the use of topological indices, pattern recognition,
and molecular orbital theory), and the remaining 500 pages
contain an assortment of references, many of which are irrelevant to modern molecular design. Lacking completely is
any treatment of really modern methods or of exciting new
approaches such as the use of neurocomputing.
The style in which this book is written is at least as eccentric as the choice of material it contains. Among other things,
we are introduced to radically new ways of spelling English
words. e.g. isomerizm (isomerism), algoritm (algorithm), approximative (approximate), occurence (occurrence), and
valance (valence). Leading workers in the field also have
their names misspelt, e.g. Bollzmann (Boltzmann) and
Boncher (Bonchev), and names always appear without accents, e.g. Randic and Trinajstic never have their accents.
British and American spellings are completely mixed up, e.g.
odor on page 748 becomes odour on page 1486 and vapor on
page 585 becomes vapour on page 620. Moreover, symbols
are used inconsistently, e.g. the Wiener index is represented
by 11‘ on page 63, but becomes W on page 181 and A W on
page 278. In addition this work contains much redundant or
useless information, e.g. we are told on page 283 that “the
boiling point temperature is known for a large number of
substances’’ and on page 747 that “more and more sophisticated methods are needed for the reduction and effective
analysis of data.” Worse still, the information that this work
proffers is often so vague as to be misleading, e.g. on page 55
we learn that “in chemistry, the symmetry plays a great role
for the estimation of structural regularities which are the
foundations of many thermodynamic systems at various
conditions” and on page 861 that “structure generation is
the inverse problem of the estimation methods for physical
properties of substances with well defined structure.” On
occasion, the text degenerates into pure gibberish, examples
of which are to be found on page 606 in the sentence: “The
molecular structures may be examined at a three-dimensional level, and studying the overlapping each other and to
compare the molecular shapes quantitatively”, and on
page 799 in the sentence: “The objective with all collected
data is to use them for establishing o r proving some phenomenon which is expected o r demonstrating that the data
d o not characterize the inter-relationships for the parameters
under study.”
In short, it may be said that Horvath’s book is a misbegotten attempt to treat the highly complex and tremendously
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~ ‘ l r c w i I. n / . E d Eiigl. 1993.32. No. 3
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fascinating subject of molecular design. The failure is to be
laid at the door of both the author and the publisher. The
author has quite clearly sought to write a work that is beyond him. The publisher should have noticed that the
manuscript was written in atrocious English and unfit for
publication. The end result is a massive book that contains
practically nothing of interest to the modern designer of
molecular species. This work deserves to be forgotten and to
sink without a trace-a prospect that is happily quite likely
in view of the great weight of this volume.
Dennis H . Rouvray
University of Georgia
Athens, Georgia (USA)
Pulsed Magnetic Resonance: NMR, ESR, and Optics. A
Recognition of E. L. Hahn. Edited by D. M . S. Buggu1e.v.
Clarendon Press, Oxford, 1992. XV, 550 pp., hardcover
C 65.00-ISBN 0-19-853 962-2
Pulsed excitation is nowadays standard for acquisition of
N M R spectra. In fact the availability of pulsed excitation
has made possible the development of most modern N M R
methods and extended the range of applications from conventional one-dimensional spectra to multidimensional
N M R spectra for structure determination of biological
macromolecules in solution, solid state N M R , and N M R
imaging. Pulsed excitation is now conquering ESR spectroscopy, following a similar route as in N M R . It is even
used in optical spectroscopy, where many phenomena
analogous to magnetic resonance can be observed as well as
additional, new effects.
Why is pulsed excitation special? Old-fashioned continuous excitation with a narrow-band irradiation source requires simultaneous detection of the response. Each frequency interval has to be measured in successive steps. By pulsed
excitation all frequency components of the spectrum are
measured simultaneously, resulting in far shorter acquisition
times o r better signal-to-noise ratios. Furthermore, excitation and detection are separated into different periods on the
time axis. Thus sophisticated pulse sequences can be developed, which are tailored to the properties to be interrogated
in the experiment. The Nobel Prize in Chemistry was awarded to Professor Richard Ernst in 1991 for the development of
pulsed N M R into a routine method and for an abundance of
pioneering new N M R methods.
But pulsed magnetic resonance was born as early as 1949
in the discovery of the spin echo by Professor Erwin Hahn,
just four years after the first successful N M R experiments. It
turned out that the echo provided confirmation of the famous
“Umkehreinwand” of Lohschmidt against Boltzmann’s irreversible increase of entropy. After the decay of the initial
pulse response, the signal could be made to reappear following a second pulse some time later. The reappearing signal is
the echo, which Erwin Hahn discovered accidentally during
his PhD work and subsequently explained and exploited for
use in N M R , ESR, and optics. The echo can be explained by
a time reversal. The decay of the echo amplitude as a function of the echo time measures the homogeneous linewidth
o r the phase relaxation time T2. This quantity is of great
interest for molecular dynamics, as it characterizes translation and reorientation processes.
A second important contribution of Erwin Hahn to magnetic resonance spectroscopy is the development of crosspolarization, the transfer of magnetization from one nuclear
species to another by matching the precession frequencies of
the two species in the applied radiofrequency fields. Here the
VCN Verlug.sgese/lsc/iuf~mhH. W-6940 Webiheim.I993
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451
Hartmann-Hahn condition must be satisfied, a rule well
known to every solid state N M R spectroscopist. These and
many other contributions to pulse spectroscopy have led to
the conclusion of Richard Ernst quoted on page 1 17 of this
book: “The influence of Erwin Hahn on the development of
time domain magnetic resonance during the past forty years
has been very significant. Even some of the roots of twodimensional spectroscopy may be found in his early work
together with Maxwell”.
Erwin Hahn reached his 70th birthday in 1991. An international symposium was held in his honor. The editor of this
book, Dr. Bagguley, spent considerable time and effort to
have many speakers of this symposium contribute scientific
articles on current developments in physics and chemistry
which have, in one way or another, been inspired by earlier
work of Erwin Hahn and his colleagues. This book is an
excellent birthday present, not only to Erwin Hahn, but to
the entire magnetic and optical resonance community. It
contains 22 contributions from well-known scientists, mainly dealing with the fundamentals and the use of echoes and
polarization transfer in N M R , ESR, optical spectroscopy,
and magnetic resonance imaging. Many of them are written
in a personal fashion, from a friend to a friend, spiced with
some reminiscences of the past. Some of the highlights are
“The Echo Phenomenon” by D. M. S. Bagguley, “Pulsed
N M R in Solids-Then and Now’’ by C. P. Slichter et al.,
“New Angles in Motional Averaging” by A. Pines et al.,
“The Multidimensional Importance of Time Domain Magnetic Resonance” by R. R. Ernst, “Spin Echoes and Thermodynamics” by J. S. Waugh, “Thermodynamics of Hartmann-Hahn Cross-Polarization” by M. H. Levitt, “Spin
Choreography” by R. Freeman, “Imaging by Nuclear Magnetic Resonance” by P. Mansfield, “Pulsed Electron-Nuclea r Spectroscopy and the Study of Metalloprotein Active
Sites” by H. Thomann and W. B. Mims, “Coherent Raman
Beats in Electron Paramagnetic Resonance Spectroscopy”
by M. K. Bowman et al., and “Optical Excitation and Detection of Spin Precession” by M. Mehring et al. The editor has
succeeded in bringing together a coherent and stimulating
account of research that has grown out of the original papers
by Erwin Hahn. The book will be of benefit not just for the
specialist, but for a wide range of students and research
workers. The practical use of the book is enhanced by a list
of Hahn’s published papers, a glossary of abbreviations, an
author index, and a subject index. It is highly recommended
for acquisition by libraries, and by individuals who enjoy
accounts of modern pulse spectroscopy with a historical perspective.
Bernhard Bliirnich
Max-Planck-Institut fur Polymerforschung
Mainz (FRG)
Chemical Information Management. By W. A . Warr and C.
Suhr. VCH Verlagsgesellschaft, Weinheim, 1992. XIII,
261 pp., hardcover D M 128.00.-ISBN 3-527-28366-8
In the preface to this book two things already become
apparent. Firstly, advantage has been taken (unusually) of
the facility for listing additional recent publications that appeared too late to be mentioned in the text. Secondly, it is
explained that the book consists mainly of a reprint of a
chapter on the same subject in Ullmann’s Encyclopedia of’
Industrial Chemistry (Vol. B 1, Ch. 12). Therefore the question at once arises as to whether double publication of this
kind is helpful from the standpoint of the reader and/or
purchaser. In this case it is, since (to anticipate the favorable
452
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VCH Verlu~szesellschuft
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verdict of this reviewer) the high quality and information
content of this text by two authors who are well known in the
field merits ensuring that it reaches as wide a readership as
possible. In my experience most chemists are (unfortunately!) not likely to seek information of this kind in “Ullmann”,
and therefore this book offers the only realistic possibility of
having it constantly to hand in the laboratory or in private
collections. The book’s high price, combined with its compactness and the demanding standard of the contents, means
that chemistry students are unlikely to buy it, but for the
same reasons no chemistry departmental library should be
without it. In contrast to the well-known guides to the chemical literature by Wolman, Mucke, Skolnik, Maizell, and
others, which concentrate on practical aspects (e.g., where
and how to seek information on a specific topic), this book
presents a survey of the whole field of chemical information
and of the basic principles that is concise, informative, and
up-to-date, but by no means limited to digital data processing. In the absence of any other suitable up-to-date and
comprehensive treatment, it could even be used as a more
advanced, though very compact, textbook on chemical information and literature sources, to follow an initial introduction using a book such as Communication, Storage and
Retrieval of Chemical Information, by Ash et a]. In addition
to giving a practically orientated guide to the literature, the
book provides the background information that is essential
to understanding the subject, and predictions about likely
future developments. The teaching institutions are notorious
for their neglect of this area of chemistry, and it is remarkable that it has been left to these two authors from industry
to fill a gap that existed.
Right at the beginning of the book one finds a very useful
and comprehensive list of common acronyms, the numbers
of which continue to grow on an epidemic scale in this as in
other fields. The comprehensive bibliography of more advanced literature is given in complete form for each chapter-this means that a particular reference can appear several
times if cited in different chapters. Unfortunately, however,
instead of giving these lists of references at the ends of the
relevant chapters, which would have made the book easier to
use and would have justfied the redundancy just mentioned,
they are collected together a t the end of the book.
The first three chapters present a concise and readable
survey of the primary, secondary, and tertiary literature. The
following two chapters are fairly detailed, and deal with
matters that often cause problems and are unfamiliar to
many chemists, namely the ‘‘gray literature” and commercial
information. Chapters 6 (“Computer Hardware”) and 7
(“Software”) are rather brief and superficial, but Chapter 8
(“Information Retrieval”) and those that follow contain
more detailed treatments appropriate to their subjects. The
chapter on data banks is a highlight of the book; all the latest
developments receive at least a brief mention, including the
SPECINFO system and the Gmelin data bank. Chapter 10,
on the handling of chemical structures, is typical, consisting
of an introduction to the basic principles with references to
more advanced reading (6 pp.), followed by a review of current developments (6 pp.) then, as the main material, a 16page description of operational systems, including relevant
PC software (although naturally the latter compilation already needs to be extended). The following chapter on “Artificial Intelligence” presents a survey encompassing neuronal networks as well as hypermedia. This is immediately
followed by a topic that might be regarded as the opposite
extreme: Chapter 12 and the subsequent ones deal with
patents and make up nearly a third of the book. The detailed
treatment of this subject is certainly appropriate to its impor-
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Angew. Chem. Inr. Ed. Engl. 1993, 32, No. 3
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