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Kinetic Processes. Crystal Growth Diffusion and Phase Transitions in Materials. By Kenneth A

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and phase transformations of alloys
and pure materials, and explain the principles and basic procedures of the methods and techniques of analysis that are
currently in use. Each chapter is accompanied by interesting practical examples, which helps the reader to understand the different topics, and makes
the text enjoyable to read. The book
also includes some practical exercise
problems and many literature references, and therefore it is very well suited
for use as a reference course book.
Kinetic Processes
Crystal Growth,
Diffusion, and
Phase Transitions
in Materials. By
Kenneth A. Jackson.
Wiley-VCH, Weinheim 2004.
409 pp., hardcover
E 99.00.—ISBN
3-527-30695-3
Andres G. Munoz
Institut fr Schichten und Grenzflchen
Forschungszentrum Jlich GmbH
Jlich (Germany)
DOI: 10.1002/anie.200485247
Energy Landscapes
The study of the fundamental processes
that take place at a molecular level
during the formation and further treatment of solid materials is pertinent to a
variety of fields, such as metallurgy,
physics, and physical chemistry. It is
sometimes difficult to present this subject in a simple manner for all scientists
in general.
This book provides a very interesting
review of the main kinetic processes
involved in the formation of new
phases and in the solid-state transformation of materials. The author has set out
to present, in a concise and easily understandable form, a detailed qualitative
and quantitative analysis of these processes on the atomic and molecular
scale, by summarizing and discussing
the main current theories. Although
each topic is introduced in such a
manner that it can be easily understood
by a general scientific and academic
readership, the author also includes upto-date descriptions of current projects
in leading research groups.
The work is a very useful reference
source for scientists and advanced students of materials science, physical
chemistry, and metallurgy. The author
discusses fundamental mechanisms
involved in adsorption, crystal growth,
1756
Applications to
Clusters, Biomolecules and Glasses.
By David J. Wales.
Cambridge University Press, Cambridge 2004.
681 pp., hardcover
£ 55.00.—ISBN
0-521-81415-4
Understanding complex systems such as
clusters, biomolecules, or glass-forming
systems is a major scientific challenge.
On a very fundamental level, these systems are, of course, governed by the
potential energy. It has become popular
to think in terms of the potential energy
surface (PES). With this approach, one
considers the potential energy as a function of the total configuration. Then the
dynamics of the complex system can be
visualized as the dynamics of a single
point on this multidimensional PES.
Why is this picture of any help? At sufficiently low temperatures the system
will mainly reside close to the local
minima of the PES. Thus, a knowledge
of the properties of the local minima
contains very important information
about the thermodynamics of the
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
system. This is a dramatic simplification
of the theoretical description, by
acknowledging that most of the PES is
physically irrelevant. In a second step,
information about the dynamics can be
extracted from additional knowledge
about the topology of the minima as
well as the saddles connecting them. If
one can find appropriate order parameters, such as the number of hydrogen
bonds in the case of biomolecules, one
can also define free-energy surfaces.
For many chemical reactions of simple
molecules, the minima as well as the
transition states are well known. In complex systems, however, the number of
minima grows exponentially with the
size of the system. Thus, one either has
to study relatively small systems, where
most if not all of the minima can be
counted, or one has to resort to appropriate statistical methods. In any event,
scientific work in this area requires a
broad knowledge of many different
aspects. Chemical knowledge enters to
define relevant model systems that
reflect a broad class of complex materials. Then elaborate numerical techniques are needed to perform the tedious numerical analysis. Finally, physical
insight is essential to analyze the large
set of numerical data and to extract the
relevant information.
Especially in the last decade, many
different groups have started to work
on characterizing the PESs of different
complex systems. The author of the
present book, David J. Wales of Cambridge University, was one of the first
scientists to perform such characterization using modern computer technology,
and has contributed in many different
ways. His influence is reflected by the
wealth of important papers in this field.
In the introductory chapter, three
different types of complex systems are
considered. 1) Clusters as aggregates of
atoms or molecules range from water
clusters, through alkali halide clusters,
to buckminsterfullerenes. Many clusters
have well-defined ground states. Important questions are related, for example,
to developing a microscopic understanding of the experimentally observed activation energies. 2) The folding of proteins is of utmost scientific relevance.
In particular, one is looking for the
origin of Levinthals paradox, which
states that the PESs of proteins have
Angew. Chem. Int. Ed. 2005, 44, 1756 – 1757
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