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Book Review Bonding and Structure Structural Principles in Inorganic and Organic Chemistry. (Series Inorganic Chemistry. Series editor J. Burgess.) By N. W. Alcock

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A chapter is devoted to a thoughtful analysis of decarbonylation reactions, the reverse of carbonylation processes.
This transformation is useful in certain situations, and clearly more work is required in this area.
The final chapter provides experimental procedures for
the synthesis of many of the catalysts described in the book.
This is a useful contribution, as is the description of methodology for the recovery of metals.
In conclusion, this impressive book is well-written, enjoyable to read, and will be of genuine value to chemists.
Cathleen Crudden, Howard Alper
University of Ottawa
Ottawa (Canada)
Chemometrics. Applications of Mathematics and Statistics to
Laboratory Systems. By R. G . Brereton. Ellis Horwood,
Chichester, 1990. 307 pp., hardcover $76.50.--ISBN 0-13131 350-9
The purpose of this monograph, which is published as an
independent volume in the “Ellis Honvood Series in Chemical Computation, Statistics and Information”, is to familiarize the experimental chemist with the capabilities and advantages of chemometric methods.
The book proceeds mainly by using simple examples to
briefly explain the principle of each of the chemometric
methods described, then illustrating how they can be applied
to real chemical and analytical problems. This approach has
the advantage that the emphasis is on understanding the
mathematical and statistical methods used. In describing
computer-based methods the author frequently gives details
of the wide choice of software that is commercially available,
and is in most cases adequate for the purpose. A brief account of the development of chemometrics is followed by an
introductory survey of up-to-date literature on chemometrics. The following six chapters describe, in a clearly organized division of subject matter, the most important chemometric methods and their applications.
The chapter on experimental design describes the use of
sequential methods such as simplex optimization, factorial
plans, multilinear regression methods and variance analysis
for the quantitative modeling and optimization of chemical
experiments. Next the author describes both well-established
methods (control card techniques, the cusum method, autocorrelation analysis) and newer methods (the autoregressive
moving average method, the variogram, the Kriging method
and the Nyquist frequency) that are used as aids in investigating time series in chemistry and for dealing with the complicated problem of representative sampling. Chapter 4 describes the many different methods for selecting and
optimizing the conditions for analyses, such as principal
component analysis, information theory, classification procedures, simplex methods, and Fourier and Hadamard
transformations. The next two chapters are concerned with
the application of univariate and multivariate methods in
signal processing. Here there is some overlapping with topics
in the previous chapter (e.g. Fourier transformation and
principal component analysis), which is an unavoidable consequence of the wide range of uses of chemometric methods.
Techniques described under the heading of univariate signal
processing include moving average calculations, deconvolution of signals and Kalman filtering. The discussion of factor
analysis as a tool for multivariate signal processing omits to
give details of the estimation of communalities; however,
Angew. Chem. I n r . Ed. Engl. 31 (1992) No. 5
6
there is a brief description of the modern method of target
transformation factor analysis. In the section on multivariate calibration some important regression methods using latent variables, such as principal component regression and
PLS regression, are mentioned but only described very
briefly.
The final chapter, which deals with pattern recognition,
includes comprehensive descriptions of unsupervised learning methods, especially algorithms for cluster analysis, and
the supervised learning methods using either “hard” (linear
discrimination analysis, linear learning machine, K nearest
neighbors) and “soft” (SIMCA) techniques, as well as
“fuzzy” methods.
The user will need to supplement the reading of the short
appendix on important mathematical operations by also
studying appropriate monographs on mathematical statistics. The appendix does not deal with the use of “robust”
statistical methods.
The typography is relatively free of errors, apart from a
few exceptions (e.g. Equation 3.5 and Table 5.20), and is very
clear. This monograph, with its clear layout of subject matter
and the easily understood and well chosen examples of applications in chemistry and analysis, offers a good basic
grounding for the experimental chemist who wishes to become involved in chemometrics; also readers who already
use mathematical and statistical methods in their area of
work will find here new ideas for applying chemometric
methods.
Jiirgen Einax
Institut fur Anorganische und Analytische Chemie
der Universitat Jena (FRG)
Bonding and Structure: Structural Principles in Inorganic and
Organic Chemistry. (Series: Inorganic Chemistry. Series
editor: J; Burgess.) By N . u! Alcock. Ellis Horwood,
Chichester, 1990. 321 pp., hardcover $ 50.95.--ISBN 013-465253-3
The introductory remarks in a book on chemical bonding
and structure can provide a very good indication of its underlying philosophy; here, in a chapter entitled “The Evidence”, the author clearly states his position: all that we
require to know are the positions of the atoms in space and
the resulting total energy. In the first forty pages the reader
is given a good brief survey of the experimental methods
whereby structural information can be obtained (X-ray diffraction, NMR, IR, electron diffraction, neutron diffraction,
etc.) and of the sorts of structural phenomena that can appear. Already one becomes aware of two things: 1) crystal
structures dominate the discussion from the start, and
2) quantum chemistry, which has now developed into a very
reliable method for determining molecular structures and
one that can no longer be overlooked, is here ignored. Moreover, the author fails to keep to the promise made in the title,
as the book is mainly concerned with inorganic solids.
In a 100-page chapter entitled “Ideal Bonds” the properties
of metallic, ionic and covalent bonds are described. The description of the underlying quantum mechanical principles is
extremely brief and lacks clarity. The LCAO concept is dismissed in a few lines. In discussing the stationary state wavefunctions of hydrogen the real and complex representations
are mixed up. The 1s wave function is given in Equation (l),
i,h(r) = 2a0 - 6.5 exp(- riao)
VCH Verlagsgesellschaft mbH, W-6940 Weinheim. 1992
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(1)
663
and this is even emphasized by putting it in a frame. One of
the d functions, although correctly drawn, is thereafter
wrongly described as d:. How could this possibly lead to a
conical nodal surface? The molecular cationic form of hydrogen is first written as H:, but then appears for several
pages as H:. Also printing errors of all kinds are scattered
through the text. We find, again within a frame, the statement: “The probability of finding an electron at a given
point is given by t+h2”. Thus no distinction is made between
probability and probability density, and as a consequence
the significance of the volume element dv is completely
ignored. The tetrahedral structure of methane is explained in
terms of hybridization, with the remark that “One electron
can easily be promoted from the 2s to the 2p level”-no
mention is made of the energy needed for this process. Is an
energy of 97 kcalmol-’ small?-and if so, relative to what
standard? Next the molecular orbitals of methane are
wrongly shown, and it is stated that the LUMO is threefold
degenerate. Space does not allow all the other inconsistencies
in this chapter to be listed. After describing several types of
double bond and the VSEPR model, Hund’s rule is stated in
such a confused way that one recognizes it only from the
heading above the frame; thus we read: “Electrons occupy
separate orbitals rather than being paired up” and “The
electrons are aligned parallel rather than antiparallel”. What
remains here of the precise formulation given by Hund in
1927, which leads directly to unambiguous statements in
spectroscopy? Finally it is even claimed that the bent structure of the NO, radical is a consequence of the Jahn-Teller
effect.
Registered mmes, rrodemarks, etc. used in rhis journal. even when nor marked a such, are not
It comes as a relief to find that the second part of the book
is entitled “Real Bonds and Real Compounds”. Here again
metals and alloys occupy a central position, but hydrogen
bonds and donor-acceptor bonds are also described. In the
second of these the “printer’s devil” has ensured total confusion by showing, in contradiction of the text, a double
occupancy for the acceptor orbital on the boron atom in the
key figure to illustrate the B-N bond. Transition metal complexes are described in detail, but the reader will fail to gain
an understanding here of the Jahn-Teller effect, since no
distinction is made between the concepts of configurations
and states. The reader can skip over a whole section on
main-group elements, as it reintroduces antiquated devices
that have long since been thrown out (the use of d-functions
for main-group elements). The same also applies to the section on aromaticity, which is based on Huckel orbitals
and completely ignores the developments of the past ten
years.
For which readers can this book be recommended? Certainly not for the chemistry students for whom the author
intended it. Instead the last 50 pages, which are the book’s
saving grace, will provide the advanced specialist in solid
state chemistry with some information on complex crystal
structures, ceramic materials, ionic conductors, ferroelectric
materials, nonlinear optics, magnetic interactions, superconductors and semiconductors.
Rudolf Janoschek
Institut fur Theoretische Chemie
der Universitat Graz (Austria)
10
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Angew. Chem. I n f . Ed. Engl. 31 (1992) No.5
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