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Book Review Applications of Dynamic NMR Spectroscopy to Organic Chemistry. By M. Oki

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Remarks on the Review Article
“Replication and Evolution in Inorganic Systems”
by Armin Weiss‘
’
By Gustaf Arrhenius, * Alexander G . Cairns-Smith, *
Hyman Hartman,* Stanley L. Miller,* and Leslie E. Orgel*
Professor Armin Weiss in a paper published in 1981 in
Angewandte Chemie has claimed observations with potential importance for the origin and early evolution of life.”’
This paper has been widely cited since it claimed experi-
[*] Prof. Dr. G. Arrhenius
A-020 Scripps Institution of Oceanography
University of California, San Diego
La Jolla, CA 92093 (USA)
Dr. A. G. Cairns-Smith
Chemistry Department
The University
Glasgow G12 8QQ (UK)
Prof. Dr. H. Hartman
Department of Earth Sciences, 54.1820
Massachusetts Institute of Technology
Cambridge, MA 02 139 (USA)
Prof. Dr. S . L. Miller
8-017 Department of Chemistry
University of California, San Diego
La Jolla, CA 92093 (USA)
Prof. Dr. L. E. Orgei
Salk Institute for Biological Studies
P.O. Box 85800, San Diego, CA 92 138 (USA)
mental proof of clay mineral replication, mutational variability in replicating clay crystals, and specific catalytic effects. The results have been invoked in support of the idea
that an inorganic evolution through natural selection preceded the evolution of organic life.
The information given in the Weiss 1981 paper is altogether inadequate for others to repeat the key experiments
that are said to be “proof of replication”. A single reference in this section reads: “Unpublished results: published
in part in G. Mai, Dissertation, Universitat Miinchen 1969;
P. Brunner, ibid. 1978; S . Fritz, ibid. 1978”.
We have been unable to trace the first and third of these
theses, while the second contains nothing which we consider of special relevance to clay replication. Nor have repeated attempts to obtain experimental protocol from Professor Armin Weiss been successful.
We now ask Professor Armin Weiss to provide us a published account of the procedures used to obtain the important results reported in his 1981 paper so that they can be
confirmed or disproved. In the meantime, his conclusions
should be accepted with caution.
Received: March 14, 1986 [Z 1721 IE]
German version: Angew. Chem. 98 (1986) 654
[I] Armin Weiss, Angew. Chem. 93 (1981) 843; Angew. Chem. Int. Ed. Enql.
20 (1981) 850.
BOOK R E V I E W S
Applications of Dynamic NMR Spectroscopy to Organic
Chemistry. By M. Oki. VCH Verlagsgesellschaft, Weinheim 1985. xii, 423 pp., bound, DM 208.00.-ISBN
3-527-26166-4
Why has a new book on dynamic N M R spectroscopy
been published when, in addition to a number of review
articles, three books are already available-the standard
work by Jackman and Cotton (1975), Kaplan and Fraenkel‘s more theoretically orientated book (1980) and Sandstrom’s recent introduction (1983) to D N M R analysis? The
title of the present book indicates that it is concerned with
applications in organic chemistry. Do the contents justify
the need for a new publication?
The introductory section describes the exchange broadening phenomenon of NMR signals, gives methods (especially approximations) which can be used to determine
rate constants, and provides typical examples of mechanisms that can result in spin exchange. Rotations around
bonds (from sp2-sp2 to sp3-sp3) are then dealt with in detail (five chapters). The following sections concern flexible
conformations in rings, the inversion and rotation of amines and imines, and applications for studying chemical
reactions.
No such survey can hope to be complete, but the author
has nevertheless managed to compile a surprising variety
of examples from extremely different areas of organic
chemistry. They reflect the current state of D N M R spectroscopy; only a few fundamental innovations have been
658
0 VCH Verlagsgesellschajr mbH, 0-6940 Weinheim, 1986
introduced in the last decade, but the technique has become an important tool for the chemist. The book serves
its purpose because it draws the reader’s attention to possible applications in his own research work and can also be
used as a reference work for literature published u p to
1983.
Several topics are, however, missing. For example, ligand permutations at central atoms, DNMR phenomena
in solids, comments on the mechanistic information obtained in multi-site exchange systems and 2D-DNMR
techniques. The computer simulation of spectra is also
dealt with very briefly, although six pages of the introductory chapter are dedicated to approximation solutions.
This somewhat underestimates the flexibility of organic
chemists as regards using new techniques.
A number of inaccurate formulations become evident on
going through the book. In the first chapter, for example,
“..., the lifetime of a nucleus in one site, ..., is a function
of the external magnetic field.”. This is impossible-what
is meant is that the lower limit of the half-life times at
which exchanging nuclei can still be separately observed is
a function of the magnetic field. Later, the diastereotopic
CH, protons in a molecule XYZC-CHAHBW are considered and the three possible staggered conformations are illustrated. This is followed by the statement: “If the free
energies of the three conformations are equal, it will be
seen readily that the magnetic environments of HA and H B
are completely equivalent on the average because ...”. This
0570-0833/86/0707-0658 $ 02.50/0
Angew. Chem. lnr. Ed. Engl. 25 (1986) No. 7
is incorrect; diastereotopic protons remain diastereotopic,
the shift difference between HA and He may be very small
or almost zero depending on the population of conformers
present, but equal energies of the conformers are neither
necessary nor sufficient for this.
These criticisms should not, however, destroy the positive overall impression made by the book. The reader’s
first impression is of a useful compendium of literature.
He may then be fascinated by a single topic and finally he
is successfully made aware of the possibilities offered by
DNMR spectroscopy for his own research.
Martin Feigel [NB 748 IE]
Institut fiir Organische Chemie
der Universitat Erlangen-Niirnberg (FRG)
Vibronic Coupling. By G . Fischer. Academic Press, London
1984. viii, 222 pp., bound, $ 42.00. - ISBN 0-12-257240-8
In recent years, the significance of vibronic coupling
(i.e., the interaction between electronic and nuclear motion
in molecules) for spectroscopy and for many dynamic
processes has become increasingly evident, as reflected in
the growing number of publications o n this subject. Accordingly, there is keen interest in a book that documents
the current status of research in this field and also gives the
nonspecialist guidance.
The monograph under consideration is primarily intended for the nonspecialist. It therefore begins in Chapter
1 with an elementary demonstration of the separation of
variables in several systems, which should facilitate a n understanding of the adiabatic approximation. In the following two chapters, this approximation is discussed for diand polyatomic molecules. In order to extend the treatment and be able to describe “intensity borrowing” and
nonadiabatic effects, variants of the adiabatic approximation and other methods, mainly from perturbation theory,
come u p for discussion. Two approaches to the calculation
of transition intensities in electronic spectra (that of dipole
length and that of dipole velocity) are compared in Chapter 4. Chapter 5 concludes the general part of the book
with a presentation of two symmetry-dependent degeneracies, the Jahn-Teller and the Renner-Teller effects, which
are classical examples of vibronic coupling. In Chapters
6-8, the most important applications come u p for discussion : the calculation of vibronic-coupling effects using
semiempirical (CNDO) methods as well as the manifestation and detection of these effects in electronic spectra and
in multiphoton processes. Important dynamic processes in
which vibronic coupling plays a role-in particular, radiationless decay-are discussed in Chapter 9. The book
closes with a survey of analogous effects in molecular crystals.
O n the whole, one can recognize the effort that the author has made to present the manifold applications of vibronic coupling in a way that is also understandable to the
nonspecialist. Nevertheless, this effort cannot be considered successful for several reasons.
First and foremost, attention must be called to the selection and organization of the material. Questions that are
only very loosely related to the subject of the book, such as
local modes, energy transfer, and unimolecular reactions,
are discussed. O n the other hand, important newer developments, such as the concept of the so-called diabatic electronic wave functions, the appearance of strong nonadiaAngew. Chem. I n t . Ed. Engl. 25 (1986) No. 7
batic effects when potential surfaces intersect conically,
and the calculation of vibronic-coupling effects using truly
ab-initio methods, are not even referred to. Furthermore,
many standard references are missing, and only little experimental material is presented to illustrate the meaning
of the effects discussed.
The material is not very clearly organized. Thus, the basic coupled equations of electronic and nuclear motion are
newly derived in each of the Chapters 2, 3, and 5 ; the socalled Herzberg-Teller expansion for the transition moment in each of the Chapters 3, 4, and 6. Without crossreferences, such repetitions are not only superfluous, but
also, at least for the beginner, even disorienting. The assignment of the material to the individual chapters is in
part illogical; Chapter 7, for example, seems out of
place-thematically, it belongs to either Chapter 6 or 8.
The unsystematic arrangement of the material makes it extraordinarily difficult to obtain a general view of the effects of vibronic coupling and of their connection. Why,
for example, in Chapter 5, which is on the Jahn-Teller effect, is the opportunity not taken to make its relation to
adiabatic potential surfaces clear by discussing calculated
model spectra? O n the whole, the book gives the impression (though unfounded) that one can almost always describe nonadiabatic effects using perturbation theory, and
it is incomprehensible, for example, why an example is
cited in Section 6.5 of the “Breakdown of the Born-Oppenheimer approximation,” precisely where this approximation does not break down.
The list of shortcomings is rounded out by the numerous
minor oversights and mistakes, which have crept into the
text. One example is the false definition of the term “electrical anharmonicity” on p. 106; a more serious example is
the discussion of the potential surfaces of a vibronic system with several nuclear vibrations, where the multimode
effect is simply overlooked (p. 84). In summary, a book
that is only marginally suited for the introduction of the
beginner to the field in question.
Horst Koppef [NB 721 IE]
Physikalisch-Chemisches Institut
der Universitat Heidelberg (FRG)
Thermodynamik irreversibler Prozesse. Eine Einfiihrung. By
H.-W. Kammer and K . Schwabe. VCH Verlagsgesellschaft, Weinheim 1985. 114 pp., Brochure, DM 28.00.ISBN 3-527-21 104-7
This thin volume addresses physicists and chemists who
wish to acquire first knowledge about thermodynamically
irreversible processes. After the Introduction, which outlines the contents of the book very briefly, a short summary of equilibrium thermodynamics is given. Next, the
fundamental concept of entropy production is introduced
by means of two examples (solidification of supercooled
water and thermal conductivity) and then generalized to
processes with a single order parameter as well as to chemical reactions. In the short, fourth chapter, the dynamics of
irreversible processes are discussed using the example of
glass transitions in polymers. This chapter seems to me to
be too complicated for a n introductory text; furthermore,
the mathematical treatment does not impart any knowledge that could not be equally well obtained in a simple
qualitative manner. The next chapter deals with Onsager’s
reciprocal relationships. Thermoelectrical effects and thermodiffusion are thoroughly discussed; on the other hand,
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