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Book Review Supramolecular Organization and Materials Design Edited by William I. Jones and C. N. R. Rao

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Angewandte
Books
Chemie
Supramolecular Organization and
Materials Design
Edited by William I.
Jones and C. N. R.
Rao. Cambridge
University Press,
Cambridge 2002.
446 pp., hardcover
$ 110.00.–ISBN
0-521-66240-0
The words ™supramolecular chemistry∫
and ™materials science∫ nowadays identify two important fields of research, the
first of which mainly involves molecular
chemists, while the second mainly involves solid-state chemists (and, of
course, solid-state physicists and engineers). Historically the two areas of
work remained separate for many years,
as the synthetic methods and analytical
techniques on which they depended
were widely different. However, in the
last few years researchers in these two
areas have increasingly been concerned
with a ™synthesis∫ of both approaches,
whereby the methods of molecular
chemistry are used to produce new types
of materials.
This book recognizes that trend by
bringing together a number of internationally renowned authors to report on
various aspects of this field of research
and review the current state of progress
in their special areas. Of course it has
not been possible within the space of 446
pages to cover the whole of the field
completely, but the book lays down the
foundations for many important directions of current research. Although it is
not a textbook, insofar as the individual
Angew. Chem. Int. Ed. 2003, 42, 255 ± 257
chapters do not directly refer to each
other, it presents the reader with a
smooth flow of subject matter, and
could certainly be used as an accompaniment to a course of lectures.
Chapter 1 indicates one direction in
which research is likely to progress in
the future. Here Addadi, Beniash, and
Weiner report on work in the area of
biomineralization concerned with biologically generated materials. Based on
the examples of the teeth of snails and
slugs, dentine, and the larvae of sea
urchins, the authors explain, step by
step, how living organisms use supramolecular chemistry to synthesize materials. Current work on biomimetic
synthesis of materials is aimed at imitating such processes in the laboratory.
In Chapter 2 Soten and Ozin discuss
the synthesis of mesoscale materials. In
the last few years there have been
enormous advances in creating nanostructures in solids. Some of the key
terms in this field are MCM phases,
quantum dots, and photonic crystals.
Many physical properties undergo
changes in the nanometer range. The
authors also introduce the expression
™panoscopic materials∫, which relates to
the synthesis of solids that show structuring on every scale of distance (from
™nano∫ to ™milli∫).
Chapter 3, by Wagner and Davis, is
concerned with the controlled production of zeolites with predetermined
structures. The authors describe studies
aimed at a better understanding of the
interaction between the template and
the silicate, and at ™designing∫ zeolites
with specific pore sizes.
Chapter 4 is perhaps the most fascinating one in the book, as it discusses the
construction of macroscopic objects. The
authors, Bowden, Tien, Huck, and
Whitesides, describe the formation of
objects with dimensions in the mm to mm
range by self-organization based on capillary forces. Such macroscopic objects
can be created from preformed components by self-assembly. Examples of
shapes that have been produced by this
mesoscale self-assembly (MESA) method include lattices, hexagons, hollow
spheres, cylinders, cubes, and helixes.
In Chapter 5 Bhattacharya discusses
organic templates for synthesizing materials, and begins by describing the
available types of amphiphilic molecules
¹ 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
(surface-active agents). The molecular
structure has a decisive influence on the
aggregation properties. Here too one
can use principles copied from the biosynthesis of such molecules (e.g., the
molecules forming the membranes of
thermophilic and amphiphilic bacteria).
Chapter 6, by Ichinose, Lee, and
Kunitake, describes how nanostructures
have been produced in surfaces by sol ±
gel processes and molecular imprinting.
It is hoped that such techniques will lead
to materials with improved mechanical
properties (e.g., abrasion resistance) or
chemical properties (crosslinking behavior, corrosion resistance, etc.). The
method is being used to produce films of
oxides or of oxide ± polymer composites.
Certain TiO2 films made in this way
generate a photochemical current and
could be a basis for solar cells. Other
TiO2 surfaces made by molecular imprinting can be used for selective adsorption.
In Chapter 7 Natarajan and Rao
describe porous structures made from
two types of zeolite analogues, namely
various metal phosphates (e.g., of Co,
Zn, SnII, and Fe), and phosphate ± oxalate hybrid structures. Both these types
of materials can be produced with
supramolecular structures by hydrothermal methods using organic templates.
Chapter 8, by Kulkarni, Thomas, and
Rao, is concerned with the self-organization of metal nanocrystals to form
larger aggregates. The large-scale process described by Whitesides and coworkers in Chapter 4 is seen here in a
small-scale version, in which nanoparticles of gold, palladium, and platinum
organize themselves into spherical packing patterns, fibers, and giant clusters. If
the nanocrystal surfaces are functionalized with thiol groups, this offers a
starting point for producing larger-scale
structures.
In Chapter 9 Newman and Jones
describe layer structures that can be
used as templates, in particular materials similar to clays in which guest
molecules can be intercalated. Such
guest species can be inorganic (e.g.,
oxoanions) or organic (e.g., surfaceactive agents). The resulting materials
can be used to make catalysts or electrodes, for example.
Chapter 10, by Raymo and Stoddart,
discusses the synthesis and properties of
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255
Books
molecular machines. These studies indicate that synthetic organic chemistry
may contribute to the miniaturization of
components such as transistors for computers of the future. Molecules (or, more
accurately, aggregates) with switching
capability are already available, having
structures based on rotaxanes or catenanes. However, attaching these to solid
substrates to construct integrated circuits will require much further development work.
The last two chapters, by Maitra and
Balasubramanian and by Bond and
Jones, are concerned with supramolecular aspects of molecular crystals. The
work in this area involves the methods
of ™crystal engineering∫, in other words
using weak interactions in molecular
crystals to control the arrangement of
the molecules in the crystal. Interestingly, Chapter 11 cites a dictionary
definition of a ™material∫ as ™any substance out of which something is, or may
be, made∫ (p. 363). Scientists or engineers working on applications of materials would certainly find that too broad
a definition and would substitute a more
restricted one.
To summarize, this is an excellent
book which has been written by competent authors and contains a wealth of
good illustrations. It is primarily suitable
for chemists, but physicists and materials
scientists will also find much interesting
and stimulating material in it. It can be
recommended for everyone whose work
is concerned with the latest developments in the science of materials.
Matthias Epple
Anorganische Chemie
Universit‰t Bochum (Germany)
In-Situ Spectroscopy in
Heterogeneous Catalysis
Edited by James Haw.
Wiley-VCH, Weinheim
2002. 276 pp., hardcover E 109.00.–ISBN
3-527-30248-4
Because of the necessity to study heterogeneous catalysts ™at work∫, in situ
256
methods have developed considerably
in the past few decades, and the field
appears ready for a comprehensive
overview. The book In-Situ Spectroscopy in Heterogeneous Catalysis, edited by
James Haw, is a collection of individual
articles on selected methods (not all of
them spectroscopies), written by specialists. The intent is to ™introduce
young scientists with training in diverse
areas∫ to heterogeneous catalysis research.
In his introduction the editor briefly
addresses the present limitations–pressure gap, materials gap, spectator species–and the impact of theory, and he
uses these issues to refer to each of the
chapters. Haw also attempts to define
™in situ∫. This section is called ™compromises∫, and accordingly the author
allows not only the ™purest definition∫
but also a pragmatic approach in which
he reduces ™in situ∫ to any study that
™teaches us about the chemistry ... under
reaction conditions∫.
All the articles have a similar structure. After an introduction to the technique a number of examples are provided. One issue is certainly how far such a
book should address the principles of the
techniques themselves. This is resolved
quite well, in that only the more exotic
techniques that are not covered in textbooks are introduced at length. A plus is
the consistent level of difficulty of the
articles. The experimentalist interested in
technical details must generally resort to
the secondary literature.
Graphs with schemes of setups or
experimental data are abundant and
make a large contribution to the quality
of the book; mostly they are well
reproduced and labeled. The extensive
use of subheadings in all chapters is very
useful, and all of these subheadings are
reproduced in the table of contents,
which thus gives a clear picture of the
structure of the articles. The table of
contents provides a better means of
finding something specific in the book
than does the index, which is characterized by mistakes and repetitions of
terms with slight variations.
The book starts with a chapter on
surface science. Its first part is dedicated
to sum frequency generation (SFG) and
nicely demonstrates the power of a true
in situ experiment, showing plots in
which catalytic and spectroscopic data
¹ 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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(from CO oxidation on Pt) are correlated. The second part of this chapter, on
STM (scanning transmission microscopy), deals with adsorbed species rather
than actual catalysis, but brings up an
important subject, that of processes
induced by the experiment itself (™tipinduced catalysis∫).
The chapter written by the editor
presents an enlightening overview of the
ways to employ NMR spectroscopy for
in situ studies in catalysis. The most
suitable nucleus that can be probed, and
thus the focus of interest, is 13C, which
delivers information on surface species
and products, not on changes of the
catalyst itself. The examples show the
tedious and often indirect approach of
this method. The author is very honest
about its limitations, admitting that
™[NMR] cannot work alone∫; which also
applies to most of the techniques, and
follows this up with an example where
an additional technique provides complementary information.
The chapter on theory gives an
overview of the principles of different
methods, leading to a tour through the
acronyms of theoretical chemistry. A
definite strength is the vast list of
references. The examples are all from
the field of acid ± base catalysis, are all
based on cluster models, and compare
the calculated energies (activation, adsorption) or NMR isotropic shifts with
experimental results.
The Raman spectroscopy chapter is
focussed on the author×s experimental
setup (UV/Raman) and work. While the
challenges of an in situ Raman application are laid out clearly, the examples
(one of which is not from the field of
catalysis) fail to demonstrate the benefits of an in situ over an ex situ experiment; they concern the nature of coke
on a zeolite and the decomposition of
lubricants upon grinding with different
tools.
The XAS chapter emphasizes technique and selected aspects thereof.
Some recent developments in cells are
not mentioned, nor are the important
rapid and dispersive XAS techniques.
The complications of the data analysis
remain sketchy and the examples are
extremely condensed. An interesting
approach to the application of in situ
techniques to monitor catalyst preparation is mentioned briefly.
Angew. Chem. Int. Ed. 2003, 42, No. 3
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