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Book Review Framework Molecular Models. Construction set with 24-page instruction leaflet

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has never appeared in monograph form. A welcome fact is
that experienced authors, known and valued for many years
in the field of organometallic chemistry, have taken this task
upon themselves.
The literature is covered as far as it has been considered in
the Russian abstracts publication (Ref. 2. Chim) up to July
1, 1963. A series of randomly chosen examples showed that
publications up to the middle of 1961 have been considered;
references from 1962 o r 1963 are seldom encountered and
concern primarily Russian papers. For instance, of the 176
references o n pages 233-239.22 are from 1959,13 from 1960,
and there are not any from 1962 or 1963. Understandably,
the achievements of Russian chemists receive a broader
treatment.
The analysis of the compounds covered is dealt with in short
sections and considers only elemental analyses and short
tables of melting points and boiling points. Analytical techniques such as spectroscopy are not included.
As a result of the preparative tone of the work, modern
structural chemistry and reaction mechanisms, which have of
late attracted greatly increased interest in organometallic
chemistry, are not done full justice. Just a n occasional
reference is made to dissociation energies.
As is the case with the other volumes of this series“], the
considerable value of the present book could have been increased by inclusion of a detailed subject index. It appears to
the reviewer that additional keywords would have been
desirable, e.g. bond energies, bond lengths, dipole moments,
dissociation, infrared, mechanism, N M R , Raman, reactionspectroscopy, stereochemistry. I n the case of Japanese
literature and patents, translations from the Russian abstracts
publication (Ref. 2. Chim.) would have been better replaced
by references from Chemisches Zentralblatt or Chemical
Abstracts.
Not least because of the chapter on the Reformatzky reaction, the book is not only useful for the organometallic
chemist, but represents a valuable reference work for all
chemists engaged in preparative work, and certainly fills a
gap in the existing literature. w, p. N~~~~~~ [NB 789 IE]
Atlas of Electron Microscopy. Biological Applications. Edited
by F. Scanga. Elsevier Publishing Company, Amsterdam
1964. 1st Edit., xxvi, 331 pp. 496 illustrations, bound,
CO. D M 118.-
Sight is man’s most important sense. Experimental work
indicates that the contours of a n object which the eye sees
distorted appear similarly distorted to the touch. It is interesting to observe the efforts made by chemists to render the
objects of their research visible, in order to be able to exercize
a measure of visual control over the results of the experiment.
It is therefore not surprising that the development of electron
microscopy has led to spectacular advances in science gener[ l ] Cf. Angew. Chem. 80, 764 (1968); Angew. Chem. internat.
Edit. 7, 744 (1968).
ally, and specially in biology, by permitting us to see a
previously invisible realm of nature.
F. Scanga, of the Istituto Superiore di Sanitii. in Rome, has
gathered together the most interesting photographs so far
taken with the electron microscope into a n atlas which is, in
its way, unique. The work begins with a fifteen-page summary of the technique and the possibilities of application of
electron microscopy. This is followed by 482 photographs of
viruses, bacteria, cell constituents, animal and plant cells,
and finally of shells.
Anyone who finds the observation or nature pleasing will
welcome this book, revealing as it does the forms and structures governing the elementary processes of life.
H. Grunewald [NB 776 IE]
Framework Molecular Models. Construction set with 24-page
instruction leaflet. Prentice-Hall, Englewood Cliffs, N.J.’
USA, D M 32.80.
The need for comprehensibility has repeatedly led chemists
to attempt to represent their molecules in the form of large,
but correctly scaled models. The best known are the Stuart
models and the stereomodels of Dreiding. Recently, in the
USA, Fieser has developed a cheaper plastic version of the
Dreiding models.
Stereomodels can also be constructed with the “Framework
Molecular Models” set. This set differs from the Dreiding
models, in that it provides no prefabricated “atoms,” but
small, rigid tetrahedra, trigonal bipyramids. and octahedra,
all made of wire rods, as well as a large number of differently
colored plastic tubes, which fit closely over the metal rods,
and which can be cut by the user to a scale of 1 A = 1 inch,
so that they represent covalent bonds or the van der Waals
radii of individual atoms. The kit also contains linear and
curved connecting rods, the latter serving for the construction of x-bonds. Twelve chemical elements may be represented
by the twelve colors of the plastic tubes. Plastic tubes marked
with two colors are provided for a number of frequently OCcurring combinations of elements (0-H, N-H, C-H. C-N,
and C-0). The coloring of the models permits the observer, as in the case of the Stuart models, to recognize
rapidly the molecular structure.
With this set it is possible to construct atomic models of the
hybridized states sp3, sp2, dsp3, sp, and d2sp3. It would be
desirable to enlarge the kit with parts that would allow
representation of hepta- and octacoordinated complexes.
For this it would only be necessary to produce appropriate
metal frameworks onto which the plastic tubes could be
fixed.
The kit has other advantages: it is easy to handle, and the
corresponding models are to scale and very clear, as they also
show the positions of free electron pairs. What is more, it is
available at a reasonable price. One would like to see this
useful set in the hands of every student of chemistry, and
would recommend it especially to everyone who has to teach
the subject, since in chemistry there is nothing to beat a good
model.
H . Grunewald [NB 711 IE]
Registered names, trademarks. etc. used in this journal, even without specific indication thereof, are not t o be considered unprorected b y law.
0 Verlag Chemie, GmbH, Weinheim
1969. - Printed in Germany by Druckerei Winter, Heidelberg.
All rights reserved. N o part of this journal may be reproduced in any form whatsoever, e.g. by photoprint, microfilm, or any other means, without
written permission from the publishers.
Editorial office: Ziegelhauser Landstrasse 35,6900 Heidelberg I . Germany, Telephone 45075, Telex 46 1855 kemia d, Cable address: Chemieredaktion
Heidelberg.
Editor: H . Grunewald . Translation Editors: A . J. Rackstraw and A . Stimson.
Publishers: Verlag Chemie GmbH. (Presidents Jiirgen Kreuzhage and Hans Scherrner), Pappelallee 3. 6940 Weinheim/Bergstr., Germany, and
Academic Press Inc. (President Walter J. Johnson), 1 1 1 Fifth Avenue, New York 3, N. Y., USA, and Berkeley Square House, Berkeley Square,
London, W. I., England.
Correspondence concerning advertisements should be addressed to Verlag Chemie, GmbH. (Advertising Manager W. ?%id). 6940 WeinheimiBergstr.,
Pappelallee 3, Germany, Telephone Weinheim (06201) 3635, Telex 4655 16 vchwh.
Angew. Chem. internat. Edit.
/ VoI. 8 (1969) / No. 4
293
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