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Book Review The Science of Crystallization. Microscopic Interfacial Phenomena. By W. A. Tiller

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and analysis, to the discovery of many new naturally occurring peptide structures, and to the elucidation of a variety of
structure-activity relationships. The careful choice of subject
matter covers all the important facts and highlights. However, it seems to this reviewer that the application of genetic
engineering methods to peptide synthesis has not been treated in adequate detail. One can hardly accept that a few more
pages here would have exceeded the planned length of the
book.
In Chapter 10 one learns that research in peptide chemistry is now being carried out in 27 countries throughout the
world (the names of about 800 peptide chemists are listed,
and the appendix contains photographs and short biographical notes on about 60 of the field’s “klite”).
A comprehensive bibliography at the end of each chapter
facilitates quick access to the original publications. Other
useful information (not only for the expert) is given in a
chronological list of international symposia on peptides
(Ch. 3, Ref. 42), and in references to the standard works on
the subject.
The “Brief History of Peptide Chemistry” announced in
the book’s subtitle turns out in practice to be a valuable
monograph on the topic. This considerably broadens the
potential readership. Scientists with an interest in the history
of the subject, especially chemists, biochemists, medical scientists, pharmaceutical chemists, and students of all these
disciplines, will find here a wealth of information that could
otherwise only be gathered with a great deal of effort. Altogether this is a book that belongs in every specialist library,
and that everyone concerned will need to have read.
Hans Jeschkeit
Institut fur Organische Chemie
der Universitat Halle (FRG)
Ashwell. Research
Molecular Electronics. Edited by G. .l
Studies Press, Taunton (UK)/Wiley, Chichester, 1992. X,
362 pp., hardcover E 44.50.-1SBN 0-86380-125-O/O-47193386-4
Molecular electronics is an intriguing term, which can be
understood to include several quite different fields of research. Essentially, however, two major areas can be distinguished. Firstly there is the search for molecular materials
that can be used in electronics or microelectronics to make
components with improved functions. Secondly one can understand it to cover various investigations, some of which
involve highly speculative ideas, with the aim of developing
a form of electronics based on individual molecules. The
hope here is that an element performing an electronic function can be incorporated within a single molecule or a small
number of molecules. It is this latter possibility in particular
that has seized the imagination of researchers. The book
reviewed here deals only with the first of these problem areas, and even here it does not claim to cover the whole topic.
A more appropriate title would therefore have been something like “Molecular Materials for Electronics-Selected
Topics”.
The six chapters are essentially independent of each other,
and cover several aspects that are important in relation to
potential applications of molecular materials in electronics.
The first chapter, “Molecular Electronic Materials”, by G. J.
Ashwell, I. Sage, and C. Trundle, begins with a 27-page
survey of such interesting topics as photochromism, electrochromism, organic conductors, superconductors, and
nonlinear materials. The most important areas of applica1536
0 VCH
Verlagsgesellschafl mbH, W-6940 Weinheim, 1992
tion are in optical data storage, molecular rectifiers, and
frequency doubling. A review as short as this is inevitably far
from complete, and many important publications do not
appear in the bibliography. This is followed by a 30-page
review of the physical and chemical properties of liquid crystals, which has no obvious relevance to the theme of the
book. The second chapter, on “Conjugated Polymers”, by
M. F. Rubner, explains conductivity in polymers by introducing the concept of solitons and polarons, then discusses
aspects such as stability and processing behavior, and describes applications of conducting polymers as active layers
in electronic components, in Schottky junctions, and in fieldeffect transistors. In Chapter 3 on “Langmuir-Blodgett
Films”, I. R. Peterson first gives a detailed description
(60 pp.) of the preparation and characterization of these
films, which allow the development of a “molecular architecture” and make it possible to arrange molecules in well-defined structures. This is followed by 15pages devoted to
potential applications (thin insulating films, dielectrics in
capacitors, in lithography, and in nonlinear photonics), the
general impression being rather pessimistic. In Chapter 4 on
“Nonlinear Optics”, S. Allen gives a good overview of the
prospects for measuring nonlinear optical properties of organic materials and influencing these chemically, and also of
incorporating such molecules into a suitable matrix. However, no practical applications in electronics are cited, which
probably reflects the true situation. In Chapter 5, “Piezoelectricity, Pyroelectricity and Ferroelectricity”, J. Sworakowski gives an introduction to this group of topics, with
particular emphasis on molecular solids. Although there are
potential applications in molecular electronics, for sensors,
storage devices, and similar purposes, the author’s view is
that, with the exception of polar monomers, these are unlikely to be realized in the near future. The final chapter by K.
Firth on “Holography” gives a short and superficial account
of the main features of holography, without really relating
this to molecular electronics. Recent developments such as
holography based on bacteriorhodopsin are not mentioned.
It is not clear for whom this book is intended. The six
chapters contain little that will be new to specialists, although they do provide something of an overview of this
broadly interdisciplinary field of research. The interested
non-specialist, although not finding as much in the book as
its title appears to offer, can nevertheless learn something
about several interesting aspects of materials research.
Hans Christoph Worf
Physikalisches Institut
der Universitat Stuttgart (FRG)
The Science of Crystallization. Microscopic Interfacial Phenomena. By K A . Tiller. Cambridge University Press,
Cambridge (UK), 1991. XXX, 391 pp., hardcover
&40.00.-ISBN 0-521-38138-9/paperback E 15.00.-ISBN
0-521-38827-9
The two monographs “The Science of Crystallization.
Macroscopic Phenomena and Defect Generation” and “The
Science of Crystallization. Microscopic Interfacial Phenomena” together form a complete set from this publisher. As the
author indicates in his preface, they are suitable as textbooks
for students at postgraduate or advanced undergraduate levels in materials science, chemistry, or related subjects. These
compact and straightforwardly presented volumes are themselves a crystallization of Tiller’s long experience in teaching
and research, during a period of far-reaching developments
0570-0X33~92jllll-l536$3.50+ ,2510
Angew. Chem. I n t . Ed. Engl. 1992, 31, No. 11
that laid the basis of modern knowledge of crystal growth
phenomena and techniques. Here the chemist, in the narrower sense of the word, may learn how complex spatial, temporal, and energetic factors influence the formation or breakdown of crystalline morphological forms, and how these
effects can be understood in terms of the chemical thermodynamics and kinetics of multiphase systems. The volume reviewed here consists of three parts. The first treats general
and specific aspects of interfacial phenomena, with examples
drawn from the semiconductors field; the second presents
“background science” relevant to both volumes (introductory discussions of phase systems, nucleation phenomena,
etc.); and the third contains example problems (although
solutions are not given).
The general discussion begins by considering research on
crystallization phenomena from the standpoint of a “response” theory, from which one arrives at a realistic estimate
of the necessary research effort (in man-years) using different approaches. This shows that if one adopts a “black-box”
approach (with the emphasis on crystal growth and experimental procedures), then the (j+ k)-dimensional space of
variables (wherej is the number of different materials and k
the number of experimental parameters) leads in practice to
an “art-based technology” (in which crystal-growing becomes an art and a collection of recipes). On the other hand,
a “system” approach based on a “clustering” that imposes a
predetermined structure leads to a “science-based technology” (with a strategically planned procedure and a minimum
of experimentation). The consequences of this viewpoint are
then systematically developed. Lastly, Tiller considers an
intelligent approach in which one chooses “scientific trajectory segments” (p. 34) and aims to minimize the experimental work required. The theoretical procedure is illustrated by
examples of experiences with semiconductor materials especially (Si, GaAs) ; these mainly involve crystallization from
the melt, and the wealth of available experimental data allows a quantitative study of the crystallization process. Although Tiller discusses the theory using examples drawn
mainly from the semiconductors field, many of the results
remain valid for the crystallization of other substances, and
under different conditions (solutions or the gas phase).
Although the chemist who frequently encounters difficult
crystallization problems is likely to find this knowledge interesting in principle, it will probably not be of great help
from a practical standpoint. For those working in the area of
crystallization, these two volumes will make interesting, and
perhaps essential, reading. On the other hand, the chemist
seeking help in this area can certainly learn from this book
about modern ideas on interfacial phenomena of crystal
growth, but should also refer to other works such as that by
K.-T. Wilke and J. Bohm (Kristallziichtung, H. Deutsch,
1988). For newly synthesized materials that need to be crystallized in order to determine their solid state properties,
thermodynamic formulas are only of limited use in general,
since one does not usually have sufficient data on the thermodynamic parameters. Thus, success is likely to come more
quickly from an approach based on the intuition of the crystal-grower, or on computer-aided empirical strategies (P.
van der Sluis et al., 1 Cryst. Growth 1991, f08, 719; G. L.
Gilliland, ibid. 1988, 90, 51).
If there is something to be said against this excellent book,
it is that a discussion of the energetic and kinetic aspects of
interfacial phenomena should have included recent studies,
by methods such as light scattering measurements and in-situ
synchrotron radiation experiments, that have shown the existence of a labile transitional region between the growing (or
dissolving) crystal and the mobile phase, and have led to a
Angen’.Chem. Inl. Ed. Engl. 1992, 31, No. 11
better understanding of its structure (e.g., R. Steiniger et al.,
J. Cryst. Growth 1991, f 12, 203; D. Cunningham et al., ibid.
1990, 99, 1065). Also, it would be worthwhile to publish a
supplementary volume giving solutions to the exercise problems, which are generally of a very high standard; these
examples drawn from practical calculations would serve to
elucidate the theoretical methods even better.
Jiirg Hulliger
Institut fur Quantenelektronic
der Eidgenossischen Technischen Hochschule Zurich
(Switzerland)
Transition Metal Hydrides. Edited by A . Dedieu. VCH Publishers, New York/VCH Verlagsgesellschaft, Weinheim,
1992. X, 399 pp., hardcover DM 182.00-ISBN 0-89573781-7/3-527-27985-7
Since Hieber’s synthesis of tetracarbonyldihydrido-iron
Fe(CO),H,, in 1931, hydrido-transition metal complexes have
occupied a central position in coordination chemistry. Complexes containing a metal-hydrogen bond are usually regarded as belonging to organometallic chemistry, due mainly to the enormous importance of such compounds in
homogeneous catalysis. For example, the role of Co(CO),H
as the catalytically active species in the Roelen 0x0-synthesis
was recognized at a very early stage, and the insertion of small
molecules into the metal-hydrogen bond has long been one
of the key reactions of homogeneous catalysis. More recently,
transition metal complexes with molecular hydrogen as
a ligand came onto the scene, following the discovery
by Kubas in 1984 of the prototype compound
[W(PliPr),),(CO),(112-H,)1.
This superbly produced book “Transition Metal Hydrides”
consists of ten review articles devoted exctusively to theoretical and physicochemical aspects of hydrido-transition metal
complexes. All the articles have been written by internationally recognized experts, who present the current state of
knowledge on hydrido-transition metal complexes in a thoroughly competent way from their own particular viewpoints.
In the first chapter Armentrout and Sunderlin describe the
results of studies on hydride species in the gas phase, and
report experimental data on the bond energies of apparently
simple binary species of the type MH. The experimental
techniques used are also described by way of introduction. In
the following chapter Sweany reviews matrix isolation studies on hydrido complexes. Particular attention is devoted to
the elementary reaction of molecular hydrogen with “naked’
metal atoms, and spectroscopic methods for investigating
metal-hydrogen interactions are critically reviewed.
The middle five chapters of the book discuss, from the
standpoint of theoretical chemistry, practically all the areas
of the chemistry of hydrido-transition metal complexes that
are currently of interest. Bauschlicher and Langhoff summarize the results of theoretical calculations on bonding in binary species of the type MH, and compare these with spectroscopic data. In Chapter 4 Hay reports on ab-initio and
semiempirical calculations on oxidative addition and reductive elimination reactions of molecular hydrogen and of saturated hydrocarbons, while Burdett, Eisenstein, and Jackson
discuss the nature of the bonding in complexes having molecular hydrogen as a ligand (“non-classical” hydrido complexes). They also discuss polyhydrido complexes, which are still
a subject of much structural and spectroscopic investigation.
Koga and Morokuma, in a very comprehensive chapter, deal
with hydrogen transfer reactions, including both intramolec-
0 VCH Verlagsgesellschaft mbH, W-6940 Weinheim, 1992
0570-0833/92/lll1-1~37
8 3.50+.25/0
1537
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