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Book Review Bimolecular Collisions. (Series Advances in Gas-Phase Photochemistry and Kinetics). Edited by M. N. R. Ashfold and J. E. Baggott

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confused. The main weakness of the book is that the author
has not been able to get hands-on experience with all the
hundreds of techniques described. As a consequence, statements in the book often reflect the subjective and optimistic
views of the inventors of such techniques.
This book is most valuable for NMR spectroscopists who
are primarily dealing with relatively small molecules for
which the tremendous variety of I D and 2D NMR pulse
sequences may be applicable. The absence of any serious
mathematics makes the book easy to read, but necessarily
makes it lacking in depth. At the end of most chapters, a
problem and answer section is included which should be
helpful to many readers. The book includes a list of commonly used acronyms plus a substantial number of valuable
references.
Ad Bux [NB 1077 IE]
National Institutes of Health
Bethesda, M D 20205 (USA)
Compact Worterbuch der exakten Naturwissenschaften und
der Technik. Band 1. Englisch-Deutsch. By A . Kuieru. Oscar Brandstetter Verlag, Wiesbaden 1989. xxxi, 1460 pp.,
hard cover, DM 130.00.--ISBN 3-87097-146-0
As a German-speaking student one spends many years
glued to school and lecture theatre benches; after this one
continues to pursue one’s subject, then suddenly it becomes
necessary to work on specialist texts in English, containing
words such as primer, multitasking, solenoid valve, drybox,
puckering, dose rate, weathering, backing, or plane-polarized. Depending on what specialized training one has had, a
few of the words may be familiar, and in some cases one may
have an idea of their meaning. But where can one look up
completely unknown words or find out their meanings with
certainty? Even with a good English dictionary one quickly
comes up against its limitations, as there is not space in such
a work to include all specialist words or specialist meanings
attached to everyday words. One therefore needs a specialist
dictionary such as that reviewed here, which was published
last year in its second, revised edition. The entries, totalling
about 117400, are mainly drawn from monographs and
specialist encyclopedias which are listed in the introduction.
However, with regard to chemistry and chemical technology
it is a little surprising that, although “Rompp” has been
referred to in compiling the dictionary, “Ullmann” has not.
The introduction also includes a glossary of the abbreviations used and an alphabetical list of the specialist fields used
as a basis for classifying the words. These two lists are also
summarized on a plastic card in the form of a bookmark;
unfortunately most of this information can only be read
when the card is not inside the book, since otherwise everything is upside-down. There is an appendix consisting of an
addendum (“carrier” and compound expressions containing
this word) and a short comparison of how scientific and
technical words are formed in English and German.
However, I would have liked to see detailed explanations
of the conventions used in the entries, e.g. what is the significance of double vertical slashes (I/), oblique slashes (/) and
dots (e.g. in “plasma.-sprayed”), and where is it explained
that in an entry such as wrap jack"..."-mode" the wavy
line stands for “wrap”, not for “wrap jack”? Also it is not
quite clear why, for example, there need to be three independent English entries corresponding to the German “Spiegeleisen” (namely “spiegel”, “spiegeleisen” and “spiegel iron”),
nor why, for abbreviated terms, the (very welcome) explana-
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Verlagsgesellschaft mbH. 0-6940 Weinheim. 1990
tion of the meaning is not reinforced by also giving the complete English expression. For example, I would find it quite
interesting to discover why fuel made from refuse is known
in English as RDF. Again, it is surprising that although
“work electrode”, “working electrode” and “reference electrode” are all included, the abbreviations WE and RE are
not, nor is “counter electrode”, which is the third type of
electrode.
The question of whether or not the German translations
are always exact is one on which I cannot give an opinion,
but it seemed to me that a few of the chemical expressions did
not quite correspond to the most common usage, e.g. “dihedral angle :Dihedralwinkel” (instead of Diederwinkel),
“methacrylic acid :Methakrylsaure” (instead of Methacrylsgure), “methyltert-butyl ether” (an unfortunate way of linking the parts of the word!): “Butylmethylether (tertiares)” (instead of tert-Butylmethylether). Whether “impact
strength” should be translated as “Kerbschlagfestigkeit”, as
given here, or as “Kerbschlagzahigkeit”, as I have been
assured by polymer experts, is something which I cannot
decide.
Unfortunately the quality of the printing in this dictionary
is not very good. For example, the first few pages distinctly
show shadows caused by double printing, and the top entry
on page 1137, “shock”, appears as ‘‘hock”. It has, of course,
not been possible to completely avoid typesetting errors, but
at least those which seriously aiter the meaning should have
been noticed. Or would you immediately understand the
explanation given for “landfall”: “Punkt, an dem der MFK
nach Flug iiber Sei die Kiiste erreicht”? First fault: the abbreviation is not explained (Marschflugkorper); second
fault: “Sei” should have read “See”. Again, “Wiener filtering‘‘, a technique used in electronic reconstruction of images,
involves not “Widerdufbau” but Wiederaufbau.
Despite these critical comments I did find the dictionary
quite useful when I used it (sporadically) over a period of
several months, specifically for looking up specialist words in
technological fields. Finally, then, for each of the English
terms mentioned at the beginning of this review I list here at
least one of the German equivalents given, although one
cannot avoid a slight furrowing of the brow here and there:
Starter, Multitasking (explained as the simultaneous execution of several tasks by a digital computer), Elektroventil,
Trockenschrank, Faltelung (!?), Dosisleistung, Freiluftbewitterung, Schutzschicht and linear polarisiert.
Elisubeth Weber [NB 1071 IE]
Angewandte Chemie, Weinheim (FRG)
Bimolecular Collisions. (Series: Advances in Gas-Phase Photochemistry and Kinetics). Edited by M . N . R. Ashfold
and J: E. Buggott. VCH Verlagsgesellschaft, Weinheim
1989. xvii, 416 pp., hard cover, E 85.00.-ISBN 0-85186393-0
The study of bimolecular collision processes at a molecular level has been extended into new areas in the last few
years, in particular through the development of sensitive
laser spectroscopic techniques capable of identifying excited
states. It has become possible to obtain detailed information
on the dynamics of chemical reactions and energy transfer
processes, and on topics at research frontiers such as the
gas-solid transition in metal clusters and the gas-liquid transition in solvent clusters, at a level which enables one to test
results from ub initio calculations.
The first chapter of the book already provides an excellent
example of the progress that has been achieved. Here Vulen-
OS70-0X33/90/080X-0936$3.50+.25/0
Angew. Chem. Inr. Ed. Engl. 29 (1990) No. 8
tini and Phillips show how laser spectroscopic techniques
such as multiphoton resonance ionization and coherent antiStokes Raman scattering (CARS) allow one to study the
classical hydrogen-deuterium exchange reaction H D, +
H D + D under single collision conditions for selected states,
and to measure rotational and vibrational excitations of the
H, product molecule for different collision energies. The
agreement between the results thus obtained and the populations of the states as predicted by ab initio calculations is
impressive. New measurements of the partial cross-sections
for the reaction H + p-H,(v = 0, j = 0, 2) + o-H,(v = 1 ,
j ) + H give sharp maxima for the formation of o-H,(v = 1,
j ) at collision energies which, according to quantum dynamics calculations, correspond to vibrational levels of the linear
H, transitional state. Valentini describes this as a “vibrational spectrum of the transition state”.
In Chapter 2 Smith describes the influence of vibrational
excitations of the reactants on bimolecular reactions, with
examples which again include the hydrogen-deuterium exchange reaction. Other examples are the reactions of F,
O(,P) and O(’D) atoms with H, and of O(,P) with HCI and
HBr, reactions with four atoms, e.g. OH + H, , OH + HBr,
CN + HCI or OH + CO, four-center reactions, and radicalradical reactions. One expects to find large increases in reaction rates following vibrational excitations, especially for
endothermic and direct reactions with “late” energy barriers,
and this is confirmed to some extent. The transition state
theory assuming adiabatic behavior as regards vibrational
energy has proved to be a useful theoretical framework for
understanding the observed effects.
In Chapter 3 Davies and Pilling describe the association
reactions H + C,H, + C,H,, CH, + CH, + C,H,, CH, +
H + CH,, 0 + OH + HO, and HO, + HO, + H,O + 0,;
here again the transition state theory of the kinetics provides
the theoretical background, as discussed in Chapter 4 by
Hase and Wardlaw. Since reactions of this type often take
place via potential wells as opposed to barriers, one cannot
assume a transition state at the position of the barrier, but
must instead use alternative definitions.
Energy transfer by non-reactive collisions is treated in
Chapter 5 by Hippler and Troe. Here the experimentally
measured quantities are the average energy transfered per
collision < A E > and the factors that influence < AE> . The
measured values can be compared with the corresponding
values obtained from quasi-classical trajectory calculations
and quantum scattering calculations. More detailed information about the dependence of the average collisional energy transfer on the excitation state of the molecule can be
obtained from other experimental methods, especially from
newer techniques such as “hot” UV absorption spectroscopy, time-resolved multiphoton IR spectroscopy, and multiphoton ionization measurements. Most of the experimental
methods used up to now give averaging over sequences of
collisions, whereas there have been very few state-specific
single collision experiments on highly excited polyatomic
molecules. Such experiments would allow a more direct comparison with theory.
In Chapter 6 Husain and Roberts describe laser spectroscopic techniques which enable one to excite lanthanoid metal atoms to particular states and then to follow their decay by
reactive and inelastic collisions in a time-resolved manner.
Reactions with oxidizing agents especially are often accompanied by strong chemiluminescence, and this can be used to
identify different reaction pathways. By comparing these results with those from ab initio calculations and with adiabatic correlation diagrams it is often possible to deduce detailed
reaction mechanisms.
+
Angew. Chem. lnr. Ed. Engl. 29 (1990) No. 8
In Chapter 7 Jarrolddeals with the preparation, characterization and reactivity of metal clusters. From this it appears
that clusters of certain sizes are particularly inert. Very little
is yet known about the effects of electronic and molecular
structure on the reactivity of clusters. The aim of these studies is to gain a deeper understanding of chemisorption and
catalysis at a molecular level.
In Chapter 8 Leone summarizes results from experimental
and theoretical studies on bimolecular collision processes for
ions in drift fields. Using laser spectroscopy it is now possible
to make detailed measurements of state populations and
spatial orientation of the ions. A correspondingly detailed
form of spectroscopy for investigating simple ion-molecule
reactions now seems to be within reach.
The book provides a critical appreciation of some current
areas of research in kinetics, together with much useful background material. In the areas with which I am most familiar
I found no gaps, inaccuracies or unreliable material. However, it is regrettable that there is scarcely any mention of the
extensive studies that have been made of inelastic and reactive scattering in crossed molecular beams. The high price of
DM 260.00 is also a drawback. To summarize, the book can
be recommended to chemists with interests in this special
field.
Karl Kleinermanns [NB 1041 IE]
Physikalisch-Chemisches Institut
der Universitat Heidelberg (FRG)
VCH TransDict, Ubersetzersoftware, Version 2.2. By Ulrich
Hellinger. VCH Verlagsgesellschaft, Weinheim 1988.
DM 780. ISBN 3-527-26873-1
Translation is an exacting process. Some call it an art,
some a craft, some a boring task. At one extreme is the
translation of, say, Paul Celan’s poetry. Celan, himself a
polyglot and a prolific translator of other poets, including
Emily Dickinson and Robert Frost, wrote in German. His
poems are often difficult to understand in the original and,
with their layers of allusion and borrowings from other languages, they are a challenge to translate. At the other extreme is the translation of the experimental protocol of a
chemical synthesis. Here, what the linguist Leonard Bloomfield termed “operationally equivalent wordings” are required. The translation should merely allow repetition of the
synthesis. However, the scientist who wants to publish in a
foreign language, usually English, most likely confronts
problems lying between these two extremes. The translation
has to be accurate, that is, free of scientific ambiguity: a
Hydrzerung in German must be translated as a hydrogenation in English and not as a hydration (Hydratisierung). At
the same time, the translation should do justice to the author’s style of writing. VCH TransDict is a potentially useful
tool for scientists and translators in meeting both requirements.
No, TrunsDict is not one of those computer programs that
translates between several languages at the stroke of the
return key. High-quality computer translation is a tantalizing goal. But not even Japan’s Fifth Generation Computer
Project, now in its ninth year, has been able to fulfill all the
needs of the scientist publishing in a foreign language.
TransDict is basically a word-processing program that also allows rapid searching of electronic dictionaries and card
files. It requires a computer operating with MS-DOS (version 2.1 or later), having at least a 640-kilobyte main memory, and equipped with a hard disk (20 megabytes or more)
and a graphics card. The pull-down menus enable the user to
Q VCH VerlagsgeseNschaft mhH. 0.6940 Weinherm, 1990
OS70-OS33/90/0808-0937$3.50+.2S/O
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