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Book Review Kristallchemie (Crystal chemistry). By J. Zemann

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energy follows, which treats the relationships between the
change in molecular geometry and the energy content. The
chapter closes with a critical discussion of conventional
molecular models.
Chapter 2, Stereoisomerism, opens with the sentence that is
fundamental to further understanding of the book: “Isomers
or structural isomers are defined as chemical species which
have the same molecular formula but differ in structure and
are separated by energy barriers”. Constitutional isomers and
stereoisomers are next distinguished (“Stereoisomerism arises
because molecules which have the same constitution may
still differ in the spatial arrangements of their atoms”) and
this is followed by the important definition: “Stereoisomers
which are related as object and nonsuperimposable mirror
image are called enantiomers or antipodes, whereas those
which are not so related are called diastereomers”. If this
widely based definition is accepted, the cis-trans olefins
designated as geometrical isomers in the past must now be
regarded as diastereomers. The chapter goes on to discuss
optical activity, including optical rotatory dispersion and
circular dichroism. A section that deserves special mention
is that describing rotational isomerism of single bonds
(conformational isomerism) in which two very useful terms
are coined. The terms enantiomeric and diastereomeric are
replaced in those cases where they refer to the stereochemistry
of the surroundings of an atom or group by enantiotopic and
diastereotopic. After a useful introduction to the stereochemistry of macromolecules, the chapter concludes with a
discussion of topoIogica1 isomerism (e.g. catenanes).
In Chapter 3 the main emphasis is placed on the development
and interpretation of the fundamentals of kinetic resolution
of racemates and asymmetric synthesis, and o n the determination of absolute configurations by both chemical and
physical methods.
A set of exercises is given at the end of each chapter, answers
following at the end of the book.
In its few pages the book provides an outline of modern
stereochemistry, and as a result the high information density
does not make for easy reading. True understanding and
appreciation of the material is possible only if the reader
works his way through the exercises, which are described by
the author as a n integral part of the book, since they are
designed to advance the student, through the inclusion of new
subject matter, beyond the descriptive material.
The broad definitions of stereoisomerism and diastereomerism are very useful for the advanced reader, but are
difficult to understand for the beginner because the subordinate terms geometrical isomerism, conformational isomerism, and “conventional” diastereomerism are used without sufficient discrimination.
Viewed as a whole, Mislow’s “Introduction” is too difficult
for the true beginner. For students preparing for their first
degree, however, the book is not only a valuable supplement
but a good textbook which offers fundamentals and results
of stereochemical research in concentrated and modern form.
In this sense the book can be recommended to all advanced
students and postgraduates. H . J. Bestmann
[NB 689 IE]
Kristallchemie (Crystal chemistry). By J. Zemann, Sammlung
Goschen, Vol. 1200/1220a, Walter de Gruyter & Co., Berlin 1966, 144 pp., 90 figures, paper covers, D M 5.80.
To fit a rapidly growing field of research such as crystal
chemistry into the framework of the Sammlung Goschen
necessitates the practice of the art of omission. The author
has deleted material in those realms in which even long
monographs and collective works prove unsatisfactory,
owing to the obvious impossibility of comprehensive treatment, e.g. in the compiling of special structural data. This
small book is intended mainly for chemists, for whom it
represents a well conceived introduction by virtue of its
lucid general chapters o n structural units and their bonding,
404
and the fundamental treatment and description of chemical
structures in the crystalline state. A desirable feature in future
editions would be the provision of space for discussing
additional material, e.g. the structure of molecules and
complexes or possibly crystallographic and chemical comparisons of transition metal compounds, for the benefit of
chemists taking an increasing interest in these problems.
H. G. v. Schnering
[NB 693 IEj
Die Anwendung der paramagnetischen Elektronenresonanz in
der Chemie (The Use of Paramagnetic Electron Resonance
in Chemistry). By L. A . Bournenfeld, V. V. Vojevodski and
A . G. Sernjonow. Translated from the Russian by K. Heuer
and Hannelore Heuer. Akademische Verlagsgesellschaft.
FrankfurtiMain 1966, 308 pages, 120figures, and 20 tables,
D M 55.-.
This book is addressed tothe readerwho wishes to use electron
resonance to solve his chemical problems. The monograph,
completed in 1961-1962 (with a few more recent additions
by the translators) consists of a predominantly theoretical
part (experimental technique, theory, evaluation of
results) and of a part dealing with the application of the
method.
A relatively large amount of space is devoted to a description
of the design principles of the spectrometer. The chemist will
generally skip this chapter because a commercial instrument
is normally available. The theory of spectra (fine structure,
g-factor and its anisotropy) in crystals is discussed in detail.
whereas the anisotropic hyperfine structure and also the
isotropic hyperfine structure are dealt with rather briefly.
The treatment of the evaluation of the spectra is biased
toward the study of crystalline samples.
Few publications, and these nlostly the authors’ own, are
discussed to illustrate applications (chemical reactions.
delocalization phenomena, radiolysis of solids, kinetics, etc.).
This method prevents the inquiring chemist from becoming
confused by a mass of individual results and directs him to
fundamentals, but it does mean that he can seek solutions to
his own particular problems only in the literature, especially
in view of the year of publication of the original edition. The
reproduction of the spectra leaves something to be desired,
and the collection of the literature references at the end of
the book makes reading more difficult. In view of the quantity of theoretical and experimental work published in the
field during recent years the book only partially satisfies the
needs of research workers in this field. For the chemist who
wishes merely to familiarize himself with the method and its
possibilities, the book will prove to be a useful acquisition.
K. Scheffrer
[NB 692 IE]
Dynamische Biochemie, Teil 11. (Dynamic Biochemistry,
Part 11). By E. Hofmann. Wissenschaftliche Taschenbiicher.
Vol. 37. Akademie-Verlag. Berlin 1966. 1st Edit. 270
pages, 38 figures, 9 tables, paper covers, DM 12.50.
Among the pocket books published in recent years those of
the Akademie-Verlag, Berlin, are distinguished by thorough,
didactic editing and scientific accuracy. The volume “Dynamic Biochemistry, Part 11” describes the fundamentals of
protein and nucleic acid metabolism and the modern discoveries about cell make-up, regulation mechanisms, and
molecular biology in a concise, pregnant, and scientifically
impeccable manner. This well written book contains a n
amazing wealth of detail and interesting biochemical comparison material for such a small volume. Complicated
relationships are illustrated by means of clear, if necessarily
somewhat abridged diagrams. Even where the scope permits
only indications, they are never given merely as keywords.
Objections to modern interpretations are also discussed,
though it has of course not been possible to take into account
the results of the last two years, which have destroyed many
Angew. Chem. internal. Edit. Vol. 7 (1968) I No. 5
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