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Book Review Fourier Transform Infrared Spectroscopy. Vol. 1. Applications to Chemical Systems. Ed. by J. R. Ferraro and L. J. Basile

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Catalysis of Hydrogen Formation from an Organic
Radical in Aqueous Solution by Colloidal Silver[**]
By Arnim Henglein[*]
Reactions between free radicals in homogeneous solution,
such as combination, disproportionation, and dismutation,
proceed with minimum rearrangement. Such reactions are
usually very fast. Organic radicals having a high negative
redox potential"] should be capable of reducing water or
of eliminating hydrogen among themselves. React ions of this
kind have not yet been observed because they are too slow
to compete with the above-mentioned radical-radical reactions.
It has now been found that 1 -hydroxy-I -methylethyl radicals
form hydrogen in the presence of colloidal silver Ag, in aqueous
solution:
2(CH3),COH
2 (CH3),C0 + H2
The yellow colloidal silver was produced by complete reduc- ~
thesolutionalsocontainingl x1W3 M
tionof5 x ~ O MAgf''],
sodium dodecylsulfate as stabilizer. In order to generate
the organic radicals, acetone and 2-propanol (each 0.1 M) are
added and the solution exposed to y-radiation with exclusion
of air. The primary radicals resulting from radiolysis of the
water react under these conditions according to
[*] Prof. Dr. A. Henglein
Radiation Laboratory, University of Notre Dame
Notre Dame, Ind. 46556 (USA)
Permanent address: Hahn-Meitner-lnstitut fur Kernforschung, Berlin
GmbH, Bereich Strahlenchemie,
Ghenicker Strasse 100, D-1000 Berlin 39 (Germany)
[**I This work
was supported by the Office of Basic Energy Sciences of
the US Department of Energy (Doc. No. NDRL-1953, Notre Dame Radiation
Laboratory).
+ (CH3),CO + H +
O H + (CH3)2CHOH
H + (CH3)ICHOH
ea;
+
(CH3)zCOH
(2)
+
(CH3)zCOH + HzO
(31
+
(CH3)zCOH + Hz
(4)
The yield of hydrogen corresponds to formation of one molecule of Hz per two 1-hydroxy-1-methylethyl radicals (corrected
for the small amount of H2 liberated from the water by
the action of the radiation). The effects observed can be interpreted in terms of the following mechanism:
+
2 (CH3)zCOH Ag,
Agi- + 2 H 2 0
2H' + 2 0 H -
2(CH3)*C0H
+
2 (CH3)$20 + 2 H + + Ag:H2 + 2 0 H 2Hz0
--t
H2
+
+
Ag.
--t
___
+ 2(CH3)zCO
(5)
(6)
(7)
(1)
The organic radicals charge the silver particles by electron
transfer, more than two electron being transferred [eq. (5)],
until decomposition of water occurs [eq. (6)]. The silver particles thus assume the role of a pool of electrons which can
be released, singly or pairwise, on demand to suitable accept o r ~ [ ~Reaction
].
( 5 ) appears reasonable because 1-hydroxy-1methylethyl radicals exhibit an anodic polarographic wave
which extends to more than -1.OV"' at negative potentials
(us. standard hydrogen electrode). A negatively charged colloidal particle is to be regarded as a microelectrode at a negative
potential according to the above mechanism.
These experiments show that short-lived free radicals can
be forced to undergo unusual reactions if they are generated
in the presence of a metal colloid catalyst in aqueous solution.
Received: March 2, 1979 [Z 212 IE]
German version: Angew. Chem. 91,449 (1979)
111
A . Henglein, Electroanal. Chem. 9, 164 (1976).
123 J . Voigt: Das kolloidale Silber. Akademische Verlagsgesellschaft, Leipzig
1929, p. 24.
[3] A . Henglein, J. Phys. Chem., in press.
BOOK REVIEWS
Intermolecular Interactions : From Diatomics to Biopolymers.
Edited by B. Pullman. John Wiley & Sons, London 1978,
1st edit., ix, 447 pp., bound, E 19.50.
The book begins with a contribution by D. Buckingham,
which is chiefly concerned with multipole expansion and
its role in the theory of intermolecular forces, treating
other aspects of the theory very briefly. We sense a little
of the fascination of the theory of intermolecular forces, with
its unexpected snares and its problems which are in part
still unsolved or have only recently been solved, when we
turn to P. Clauiere's report, and in particular to the first
part, which deals with the basic aspects of the theory. The
author can in part refer to his own work here. The second
part is concerned with the derivation of approximate formulas
for individual contributions to intermolecular forces in large
molecules. The bibliography is impressive. In R . Rein's article,
so broad is the theme of the book, he describes the interactions
of nucleic acids, and in particular hydrogen bridges and dispersion forces between superimposed base pairs. Finally, P.
Schcister gives a very useful survey of ab initio calculations
418
for hydrogen bridges. He begins with a critical assessment
of calculations on isolated components, and goes as far as
hydrogen fluoride polymers (HF),. A whole series of physical
properties and the way in which they are affected by hydrogen
bridges are discussed; much attention is paid to an analysis
of the calculations and to a qualitative interpretation of the
results.
In all, the book can be recommended to anyone interested
in the theory of intermolecular forces.
Werner Kutzelnigg [NB 454 IE]
Fourier Transform Infrared Spectroscopy. Vol. 1. Applications
to Chemical Systems. Ed. by J . R. Ferraro and L. J . B a d e .
Academic Press, New York 1978, 1st edit., viii, 311 pp.,
bound, $ 25.00.
This is the combined work of a series of well-known authors.
It is divided into seven chapters, which are largely concerned
with applications:
1. Study ofmatrix-isolated species (D. W Green, G . 7: Reedy);
2. Study of synthetic and biological macromolecules (L. D'EsAngru Chem l n t E d Enql I X ( 1 9 7 9 ) N o 5
0 Verlag Chemre, GmbH, 6940 Weinhelm, 1979
0570-083~179'0j05-0418$ 02 5OjO
posito, J . L. Koenig); 3. Emission measurements ( J . B. Butes);
4. GCIIR Coupling (P. R. Grij”iths); 5. Study of materials
under high pressures ( J . L. Lauer);6. Far infrared spectroscopy
( J . R, Durig, A. W Cox); 7. Environmental protection, Space
research and energy research ( J . R. Ferraro, L. J . Basile).
Each chapter describes the application of IR spectroscopy
to the solution of specific and demanding problems, and is
illustrated with many examples. Most of these problems have
been known for some time, and were dealt with in the sixties
and earlier by means of conventional dispersive IR spectrophotometry. To do this, it was often necessary to operate
at or beyond the capability limits of the instruments. The
introduction of the Fourier technique considerably extended
the possible applications of IR spectroscopy. The aim of the
present book is to demonstrate these wider applications, and
this is certainly achieved qualitatively. The book also offers
many valuable technical tips not directly connected with the
Fourier technique (cell construction, sample preparation, evaluation of the spectra, etc.). However, it is a pity that there
is no chapter dealing in general terms with the advantages
and disadvantages of the Fourier technique as opposed to
the conventional dispersive method, where the various problems (microsamples, FIR range, heavy background losses,
rapid measurements, etc‘.) could be considered. Without such
a chapter an impartial reading of this quite heterogeneous
work could lead to the conclusion that any problem which
can fit into any of the seven chapters requires the use of
the Fourier technique. Such a conclusion is undoubtedly valid
in the case of GCjIR coupling and in the problems of space
research, to name but two examples, but it is completely
unjustified e.g. in the case of the study of matrix-isolated
species and of synthetic macromolecules in the medium IR
range. This is shown by the flood of excellent papers which
describe work in this field, where the conventional dispersive
instruments are used just as much as ever. The book should
have provided a clearer answer to the question when a user
might need, o r be able to exploit, the dearly bought advantages
of the Fourier technique.
Erick Kndzinger [NB 4491
Stereochemie und Konformationsanalyse (Stereochemistry and
Conformational Analysis). By J . Dale. Verlag Chemie, Weinheim 1978. xii, 208 pp., bound, DM 38.00.
From its title the book promises to be a comprehensive
presentation on these two important sectors of chemistry;
the promise, however, is fulfilled only as far as the second
part of the title is concerned. Conformational analysis is treated
in detail taking as a basis the physical methods used. Almost
half of the book is devoted to the conformational analysis
of cyclic compounds. This section is logically arranged, and
both students and experienced scientists and lecturers can
learn something from it.
In the first part of the book, however, the geometric foundations of stereochemistry are missing. No effort is made to
present clear definitions. The use of models, a requirement
in all scientific work, is especially important in stereochemistry.
This certainly does not mean that rigid geometric objects
can give a true-to-life representation of molecules (or of large
numbers of molecules), but geometric models d o make it
possible, with the necessary degree of caution, to work out
the fundamentals of modern stereochemistry. This is true not
only for the structure, configuration, and conformation of
molecules, but also for the symmetry relationships of constitutionally identical groups within a molecule. These relationships
play an important role, for example, in NMR spectroscopy
and in enzymology. When we find the assertion on page
32 that “The presence of a chirality center allows the geminal
Anyrw. Ciiern. l i l t . Ed. Eilyl. 18 (1979) N o . 5
protons o r groups to be nonequivalent (diastereotopic or prochiral)” then we understand why clear definitions of these
expressions have been avoided.
On the other hand, the physical methods, and in particular
the spectroscopictechniques used to determine molecular properties, are described carefully and in detail. The section on
asymmetric induction is inserted somewhat unexpectedly after
the section on cyclization of polyenes (p. 100).
Although the book is not written in such a way as to
arouse any great enthusiasm, it can be recommended to interested readers. One should not, however, be under the illusion
that the long-awaited standard work on stereochemistry has
at last arrived.
Junos RPtey [NB 465 IE]
Surfactants and Interfacial Phenomena. By M . J . Rosen, John
Wiley & Sons, New York 1978. 1st edit., 304 pp., bound,
$ 30.45.
Because of the increasing importance of interfacial phenomena, particularly in connection with detergents, the literature
concerned with these problems has increased markedly over
the past few years.
The present book attempts to provide a compact summary
of the most important interfacial and colloid chemistry aspects
of the use of surfactants. In ten chapters the author discusses
the general properties and structures of surfactants, their
adsorption at interfaces, micelle formation, solubilization,
reduction of surface tension, wetting, foam properties, emulsification, dispersion, and washing.
The author has succeeded very well in his aim of providing
the essential information for the interested reader in a restricted
space. Careful selection of the material permits the important
relationships to be recognized ; the book is not weighed down
with marginal data and information.
The work is intended for advanced students and for practising scientists who want a compact guide to the properties
of surfactants. At the end of each section there is a selection
of literature references to enable the topic to be studied further.
It is worth noting that the literature references cover the
appropriate European and Japanese literature, which is not
always the case with English-language monographs.
The present book will completely fulfil its purpose of offering
both the interested subject specialist in the chemical industry
and also the advanced student the opportunity of obtaining
the essential information on surfactants and their behavior
at interfaces.
M . J . Sdiiziigw [NB 447 IE]
Internal Rotation and Inversion. An Introduction to Large
Amplitude Motions in Molecules. By D. G. Lister, J . N .
Mucdonald and N . L. Owen. Academic Press, London 1978,
1st edit., xii, 246 pp., &, 11.50.
This book attempts (in itself a praiseworthy aim) to present
the multiplicity of specific experimental and theoretical
methods for the investigation of the internal mobility of molecules, together with the results and insights gained therefrom, to a broad non-specialist audience. Vibration and rotation spectroscopy, and also small rotation barriers, are treated
in comparative detail, while the methods for the barrier range
of25 to 100kJmol- are only mentioned cursorily. One chapter
contains a few remarks about empirical force-field and quantum-chemical calculations of barriers. The book closes with
a discussion of atomic inversions, pseudorotations, and other
motions in rings, and with a brief look at macromolecules
of biological significance.
’
419
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