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Book Review Electronic Conference on Trends in Organic Chemistry ECTOC 1. Edited by H. S. Rzepa C. Leach and J. M

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BOOKS
Abstracts on CD-ROM-The
Crystal Structures. I: Patterns and
Symmetry. By M . O‘Keeffe and
B. G. Hyde. Mineralogical Society
of America, Washington, DC, 1996.
453 pp., hardcover $36.00.-ISBN
0-939950-40-5
The contents of this book are: “Preface
and Note to the Reader” (6 pp.), “Symmetry in Two Dimensions” (27 pp.),
“Three-Dimensional Point Groups” (30
pp.), “Three-Dimensional Space Groups”
(41 pp.), “Lattice Geometry” (33 pp.),
“Polyhedra and Tilings” (66 pp.),
“Sphere and Cylinder Packings” (81 pp.),
“Nets and Infinite Polyhedra” (92 pp.),
Appendices (64 pp.), Book List (2 pp.),
and Indices (7 pp.). The appendices as
well as notes and exercises at the end of
each of the chapters provide additional
material for study. The scope of the book
is narrower than the title would suggest. It
deals with inorganic crystal structures of
interest to the solid state chemist.
Crystallography has been too successful recently. If you can raise a few hundred
thousand dollars you can buy a black box
(an automatic single crystal diffractometer). At the push of a button most crystal
structures can be solved without any
deeper understanding of the scientific
background involved. This results in a
flood of published crystal structure data
that tell us how atoms arrange in space.
Unfortunately these data cannot be assimilated without (according to the preface) “. . .learning the methods appropriate
to describing infinite periodic objects.
These methods are generally unfamiliar to
those who are not professional crystallographers (a fact that greatly hinders the development of solid state chemistry) and
one of the aims of this book is to provide
a usable introduction to them.” The vol-
/
This section contains hook reviews and a list of
new hooks received by the editor Book reviews are
written by invitation from the editor. Suggestions
for books to he ireviewed and for hook reviewers
arc welcome Publishers should send brochures or
(better) books to the editorial office. Redaktion
Angewandtc Cheniie, Postfach 10 11 61, D-69451
Weinheim. Germany. The editor reserves the right
of selecting which hooks will he reviewed Uninvited hooks not chosen for review will not he returned
New Age?
ume is meant by the authors “as a textbook for courses and as a general reference”. The necessary basic tools of
crystallography are introduced in the first
four chapters. That covers the symmetry
part of the subtitle. The remaining three
chapters deal with the patterns of inorganic crystal structures, that is with polyhedra, tilings, packings, and nets, and
they contain some new material. The
short book list is well annotated, but even
with the few references interspersed
throughout the text it is insufficient as a
guide for further study. One electronic
data base is listed (Inorganic Crystal
Structure Data) and is judged as rather
imperfect, but still as excellent value for
money. However, the equally important
data base for metals, CRYSTMET, is
omitted (a pity since intermetallics figure
prominently in this volume). The incomplete indices are woefully inadequate and
will unfortunately hamper the use of the
volume as a general reference source.
Thus, a notation is introduced for “coordination numbers” (p. vi). the term is used
in the text (e.g., between pp. 208 and 2 5 9 ,
but it is not entered in the subject index.
The related topic of filling of interstices
comes up in the text, but cannot be located via the subject index under “filling”,
“stuffing” or “interstices”. The term “rutile” has four references in the index, but
in fact shows up at least four more times
(on pages vi, 82, 220, and 321).
The attempt to cover many aspects of
basic crystallography and the tools of
crystal chemistry within one book (the authors call this the “split personality” of
the volume) means that both goals suffer
from a lack of the space necessary for a
thorough exposition. As a textbook for
self-study by neophytes it seems to be too
concise. It might be useful as ancillary
reading in courses on solid state chemistry
and the like. For experienced workers it
will be fun, much appreciated, and very
instructive in its last three chapters (which
cover more than one half of the book).
There they will find, after some searching
(which should be entertaining in itself),
many a nugget of information out of the
rich store of the authors’ knowledge. The
fun part comes also from the idiosyncratic
nature of the book and from the less-than-
pompous language used by the authors
(“why, for heaven‘s sake” on p. 270, when
questioning the popular view on the reason for the occurrence of close packed
structures). At its price, Crystal Structures is certainly a good buy.
WcJrnerH. Baur
Institut fur Kristallographie
der Universitat
Frankfurt am Main (Germany)
Electronic Conference on Trends in
Organic Chemistry, ECTOC 1. Edited by H. s. Rzepa, C. Leuch and J. M .
Goodman. Royal Society of Chemistry, London, 1996. CD-ROM
E 50.00.-ISBN 0-85404-899-5
So, the virtual conference has finally arrived. N o more long trips to Tokyo,
Rome, or Jerusalem to discuss new ideas
with other scientists working in the same
field. By using the Internet via a laptop we
can now take part in conferences from the
work-desk or even from home. Actually,
of course, it has not quite reached that
point yet, so d o not worry. Although the
expression “Electronic Conference’’ may
at first conjure up an image of such a situation resulting from the use of new media,
the reality is slightly different. As will become clear below, the purpose of an electronic conference is essentially to complement and report on an actual conference.
The growth of interest in electronic
conferences in the last few years has largely been due to developments in the Internet, which has changed from being a textorientated medium based on services such
as e-mail, telnet, and ftp, to a multimedia
network (the Worldwide Web, www).
This transformation has opened up new
possibilities for handling information, especially in the natural sciences. Lectures,
posters, and discussion sessions taking
place at a conference can now be recorded
fully in electronic form, and transmitted
without any loss of information in HTML
format (hypertext markup language).
Three-dimensional molecular models
embedded within the text can be moved
and rotated on the monitor screen. Dynamic processes can be shown as animat0570-0833~Y7/3612-1353$17 50+ 50 0
1353
BOOKS
ed images, spectra can be compressed,
stretched, or edited in other ways, and so
on. By using the hypertext transfer protocol (HTTP), documents from any computer can be loaded onto the Internet, regardless of the operating system that they
use or the computer platform. The only
requirement for all these operations is that
the client browser’s plug-in is capable of
recognizing the standardized data structure of the application concerned.
The first Electronic Conference on
Trends in Organic Chemistry, ECTOC 1,
was organized by one of the pioneers in
the field of standardization of chemical
information, Henry S. Rzepa of Imperial
College, London, together with his colleague Christopher Leach, and Jonathan
M. Goodman (Department of Chemistry,
Cambridge University), and is published
in a CD-ROM version by the Royal Society of Chemistry.
The conference proceedings consist of
six “keynote papers” and 71 articles,
which present recent results (up to mid1995) in the areas of synthetic, mechanistic, and biological chemistry. The authors
are from 13 countries. On reading the
keynote papers one immediately appreciates the advantages of the HTML format.
A mouse-click on one of the two-dimensional valence bond formulas that are displayed brings up a three-dimensional image of the molecule that can be rotated at
will, an extremely useful facility for complicated structures. These 3D structures
are filed as Cartesian coordinates in the
format of the Brookhaven Protein Database (*.pdb files).
Taking as an example the contribution
“A New Synthetic Route to the Illudin
and Pterosin Family of Sesquiterpenes”,
by Albert Padwa, Erin A. Curtis, and Vincent P. Sandanayaka (Department of
Chemistry, Emory University, Atlanta),
the key structure can be viewed from any
direction and in many different representations (wire model, stick model, stickand-ball model, space-filling model, etc.) .
The coordinates (from an X-ray crystallographic analysis) on which this is based
are those of a precursor of illudin, which
already has all the five benzene ring substituents of the later products, with the
correct regiochemistry. Moreover, a novel
feature of the HTTP approach is that one
can then go on from this 3D presentation
to edit the data. Once the coordinates
from the X-ray data have been stored locally on the hard disk of one’s PC, the way
is clear for further data processing such as
energy calculations.
In the contribution “Studying Perturbation Theory with Explorer EyeChem
and VRML”, by Guillermo A. Suner,
1354
,G
Omer Casher, and Henry S. Rzepa, the
imaging of structures is taken a step further. These authors have translated the
semiempirical (AMI) calculated transition state structures for a large number of
Diels-Alder reactions into the VRML
format (virtual reality modeling language). This allows one to move around
in the virtual space of the calculated structures and study the overlapping of the
frontier orbitals. This technique opens up
new perspectives, in the truest sense of the
word, and has great possibilities for use in
teaching.
Most of the other contributions use
only HTML text and graphics in the GIF
format. They range over many different
areas of organic chemistry, from new syntheses of natural products and enantioselective catalytic reactions, via the chemistry of fullerenes (where, incidentally,
pdb coordinates would have been ideal),
to new nonlinear optical materials and to
purely theoretical studies. The work includes a full list of contributions to the
discussions of the individual presentations and a list of participants (with photographs in some cases), making altogether a very successful CD-ROM. Within the
next five years we may witness the disappearance of the conventional printed
“book of abstracts”.
Jorg Grunenberg
Institut fur Organische Chemie
der Technischen Universitat
Braunschweig (Germany)
pH and Buffer Theory - A New
Approach. (Series: Solution Chemistry, Vol. 1.) By H . Riibe. John Wiley
& Sons, Chichester, 1996. 192 pp.,
hardcover E 40.00.-ISBN
0-47196735-1
This subject has traditionally been a favorite area of research for Scandinavian
chemists, and H. Rilbe is on familiar
ground in this book. The author’s claim to
present a “new approach” refers essentially to a general procedure for treating all
types of problems in this field. According
to this, all the quantities that occur in pH
and buffer theory, such as concentrations
and equilibrium constants, are converted
into dimensionless logarithmic numbers,
so as to benefit from the well-known
mathematical simplifications associated
with the use of logarithmic relationships.
Despite this, however, as the arguments
are developed in greater depth the equations quickly become very complicated.
Consequently the author’s presentation
comes over as rather dry and leaden on
the whole, although that is partly due to
VCH Verlagsgesel1.schaftmbH, 0.69451 Weinheim, 1997
the nature of the subject. Another disadvantage of the author’s new approach is
that, because of the special expressions
that are used, one cannot simply begin
reading at a chosen place in a chapter or
section of interest; instead one must first
search back in the book to work out the
definitions. Many of the results have been
published before by the author in specialist journals, and thus the book is a summary and consolidation of that work.
Chapter 1 begins by introducing the
concepts of pH and the relevant equilibrium constants. For each of the aspects that
are treated from a stoichiometric standpoint the author then goes on to discuss
the thermodynamic relationships involved. Buffer solutions consisting of a
single-proton weak acid combined with a
strong base, or a weak base with a strong
acid, are considered next. Here the reader
meets the difficulty already mentioned
above, as one needs to be familiar with the
author’s definitions in order to fully understand the curves that are shown.
Chapter 2 deals with two-proton protolytes and their salts with strong acids
and bases. Here the ionic strength of
buffer solutions is also considered.
In Chapter 3 the author guides the
reader through the Scylla and Charybdis
of mixtures of weak acids and weak bases,
offering first an approximate solution to
the problem and then a more rigorous
analysis. Here, as in the other chapters, he
mentions alternative approaches used by
other authors and considers the strengths
and weaknesses of the different methods.
Chapter 4 treats acids with three or
more protons and their salts. Special attention is devoted to the differences between the K-values and how these affect
the buffer properties. The main topic of
Chapter 5 is the Debye-Huckel theory
for strong electrolytes and its application
to the calculation of activity coefficients.
Chapter 6 is entirely devoted to the buffer
properties of water and the associated
titration curves. This is followed by a
chapter on experimental methods for determining pK- and ApK-values and isoprotic (or isoelectric) points. Finally there
is an appendix containing some computer
programs for determining isoprotic
points.
This book, written by a well-recognized
expert in the field, is intended for the specialist rather than for the student, as indicated by the absence of exercise problems,
and not least by its price. It takes up from
the point where the usual introductions to
quantitative analysis leave off, and assumes that one is already familiar with
ordinary buffer theory. The question of
whether one can begin to accept the nota-
057o-0X3319713612-I354 $ 17.50+ .SO10
Angeu.. Cizrm. Inr. Ed. Engl. 1997, 36, N o 12
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