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Book Review Absorption Spectroscopy of Organic Molecules. By V. M. Parikh

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(significator) of the molecular signification (signified) either
sequential, structural, etc.”-but
also : “Allomones. Coactones (q.v.), ...;Coactones. Ecomones (4. v.), ...;Ecomones ....”;
etc. All 110 pages are loaded with this kind of freight, which
makes severe demands on the reader. The intention is to
bring systematic order into the presentation iof phylogenetic
development, in which the evolution of life is assumed
to be from simple biomolecules by asymmetric, autocatalytic,
and aggregating forces. The molecular processes occurring
during phylogenesis of organisms (“diachronic molecular
epigenesis”) are mostly considered on the basis of cellular
chain molecules (“metabolic catenary biosyntagmas”) which
become better suited to their structure, function, or
regulation, and more versatile, by lengthening or shortening,
branching and ramification. The causes are point mutations,
feedback, selection, gene duplication, etc. Useable biomolecules
thus function after self-aggregation into structures of higher
order on the physiological and ecological plane. The author’s
phenomenal knowledge of the facts and historical perspectives
and his intellectual insight into his material can only be
marvelled at-nly
the preparation of the dish makes it hard
to digest.
The subsequent vegetarian fare is simpler and more heartwarming, the more so since it is spiced with anecdotal asides.
Plants and animals are of the same age on the evolutionary
time-scale, but the former have adapted themselves much
more intelligently-being bound to one place-in order to
come to grips with their living space. While animals differ
little in their fundamental biochemical capacities-but
all
the more so in their controlled types of behavior-plants
produce a highly diverse range of materials that make their
survival possible. The development and the distribution of
cellular macromolecules, the primary and secondary constituents of the plant kingdom, are discussed and it is brought
out how the various secondary biosynthetic routes determine
which niche the given plant will adopt in the ecosystem.
Change is the mother of evolution and woe betide him who
attempts to confine biochemical evolution in a procrustean
bed! In this volume the promised standard of content and
production is maintained; it is announced that the second
sub-volume will deal with the molecular evolution of bacteria
and animals; after that there will still be seven further volumes
before the whole series is complete.
L. Jaenicke
[NB 247 IE]
Absorption Spectroscopy of Organic Molecules. By K M . Parikh. Addison-Wesley Publishing Co., Reading, Mass 1974.
1st Edit., x, 325 pp., paperback $! 10.75.
Since the intrusion of modern spectroscopic methods into
all subdisciplines of chemistry, and thus into general training
programs for chemists, there has been no lack of attempts
to write books presenting these techniques in a simple manner.
We have noted a total of about 20 titles intended as an
introduction to these methods for students.
c! M . Parikh has now written a further book of this kind.
Following upon a general introduction to spectroscopy he
deals with UV, IR, and NMR spectroscopy, and mass spectrometry in four sections, dividing the material into general/theory, instrumental and evaluation of spectra. Then come
a section on the identification of organic compounds with
examples and an appendix of tabular surveys (IR and NMR
assignment tables etc.). Each chapter closes with test questions
and a bibliography which is quite extensive in some cases.
Unfortunately, the book which is clearly intended for students,
contains a number of failings likely to confuse the beginner
but unlikely to distract the expert. Thus some of the IR
Angun..
Chrm. intrmur. Edit. f Vol. 14 I I Y 7 5 ) f N o . 3
spectra exhibit precisely those mistakes which are symptomatic
of the beginner and whose elimination can be regarded as
the primary task of such introductory books (“negative absorptions”, excessive amounts of sample, etc.). Moreover, the NMR
spectra are poorly reproduced (very dark background, poor
plotting). In some of the spectra the integration can only
be recognized with difficulty. In addition, references to journals
unlikely to be found in college libraries (e. g. Phil. Mag., Sov.
Phys. Tech. Phys., Vacuum, J. Sci. Instrurn.) will be of little
to help to students. Hence the book has to be pigeon-holed
somewhere between an introduction and a monograph and
can only really be recommended to those concerned with
the teaching of instrumental analysis. Such readers may indeed
profit from a variety of ideas found in the book.
Egon Fahr [NB 242 IE]
Orbitale organischer Molekiile (Orbitals of organic molecules).
By W L. Jsrgensen and L. Salem. Translated by E. Konig.
Verlag Chemie GmbH, Weinheim 1974. 1st Edit., x, 294
pp., 1180 figures, bound DM 32.-.
The authors intend this book (original edition: The Organic
Chemist’s Book of Orbitals, 1973) for “a new generation of
chemists eager to understand molecular structure at the
electronic level”. They begin with an introduction (44pages)
to the qualitative construction of 0- and x-type molecular
orbitals from group and bond orbitals, while assuming
their “reality” and practical “utility”, ask for chemical
applications, and cite references for further reading (76 titles)
including such topics as the frontier orbital and the relaxability
methods.
The comparison of qualitative orbitals with the perspective
computer plots of contours of eigenfunctions obtained by
extended Hiickel or open-shell MINDO/2 calculations presented on 226 pages is impressive. Clarity is enhanced by
suitable normalization, avoidance of changes of perspective,
and the use of solid and dashed contours. Skillful arrangement of the very complicated drawings permits combination
of the sets of orbitals to give projectable pictures and supplementation by the tabulated occupations. Details concerning the
calculation are given for all examples of 104 conformers of
95 molecules (1 4 containing no carbon atom) with 2 (hydrogen)
to 36 (cyclohexane, norbornadiene) valence electrons, and new
molecular geometries are cited. In all except four cases, all
occupied and several unoccupied (2.4 on average) orbitals
are depicted, with group-theoretical and, wherever sensible.
orbital type designations, and assignments to known ab initio
orbital energies. It is accepted that the various methods of
calculation may also differ with regard to the geometric
parameters. This fact alone should induce one to compare the
orbital sequences thus defined with results or interpretations of
photoelectron spectroscopy.
Notwithstanding a number of unclear points in the translation
and the occasional rather unfortunate choice of terms (e.g.
“Athyl-Radical, halbiert” or “Benzol, Dewar-Form”) the book
is eminently suitable for the illustration of semi-empirical
wave functions in the teaching of quantum chemistry.
Gerd Kaupp
[NB 244 IE]
Lehrbuch der Organischen Chemie. (Textbook of organic
chemistry). By R . 7: Morrison and R. N . Boyd. Translated
by I . Mayer-Ruthardt. Verlag Chemie GrnbH, Weinheim
1974. 1st Edit., xxxiii, 1392 pp., 225 figures, 46 tables, bound
DM 78.-.
The present German translation of the third edition of
“Organic Chemistry” will be of great value to chemistry stu191
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