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Book Review Introduction to Theoretical Organic Chemistry and Molecular Modeling. By W. B. Smith

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BOOKS
tion used in the book is for the reader to
decide. It remains to be seen to what extent the proposed new approach will be
taken up in research and teaching.
Bernhard Neumiiller
Fachbereich Chemie der Universitat
Marburg (Germany)
Introduction to Theoretical Organic
Chemistry and Molecular Modeling.
By W B. Smith. VCH Publishers,
New York, 1996. 192 pp., hardcover
DM 89.00.--ISBN 1-56081-937-5
Computer programs for quantumchemical calculations are becoming increasingly user-friendly, and consequently
chemists with limited theoretical knowledge are using them more and more often.
It is all too easy for non-theoreticians to
be misled by the suggestive power of the
attractive graphics. so that they overvalue
the information content of the results that
the black box turns out with so little effort. For these users there are only three
possible ways out of this dilemma: 1. leave
well alone; 2. work in collaboration with
colleagues; or 3. acquire the necessary
theoretical knowledge by private study.
This book by W. B. Smith is intended to
help with the third alternative.
It is certainly a welcome development
when an attempt IS made to present theoretical organic chemistry at such a level
that it can be understood by most nonspecialists. Although there are many excellent books on the quantum-mechanical
fundamentals of chemistry, few of these
offer help in the practical application of
theoretical methods. In accordance with
the title of this book, the author’s idea is
first to introduce the reader to the theoretical fundamentals of quantum chemistry
(qualitative MO theory), then in the second part (from Chapter 7 onward) to treat
the most commonly used theoretical
methods, and this approach is undoubtedly correct.
However, it must be said at the outset
that neither the first nor the second part is
suitable as a student textbook. The choice
of subject matter and the strong emphasis
placed on the Huckel theory give cause for
concern. It is true that in a treatment of
such a complex topic as this within a mere
Angebv. Clwn. hi.Ed EngI. 1997, 36, No. 12
192 pages, one has to be prepared to accept some compromises. Nevertheless, the
mathematical derivations must be errorfree, understandable, and entirely consistent. This book contains so many errors,
loose and careless statements, and lapses
from rigor in the physical arguments, that
a newcomer to the subject is at risk of
failing to follow the discussion o r getting
an incomplete picture. A few examples
will illustrate this. The first is the derivation of the Schrodinger equation in a few
steps on pages 2 and 3. The transition
from classical mechanics to quantum mechanics is made, without further explanation, by replacing the momentum in the
classical expression for the total energy by
the corresponding quantum-mechanical
operator, then multiplying the expression
by a wave function which appears from
nowhere. Arguments of this kind d o not
help towards an understanding of the
quantum theory. The symbols used for
variables are not always consistent. On
page 3 the symbol \i/ is used for the total
wave-function, whereas on page 4 it represents the basis orbitals. Later we find that
Y is used for molecular orbitals, whereas
in the description of the S C F methods (p.
109) Y represents the total wave-function
and \i/ a molecular orbital. As the text contains no mention of the changes in meaning, the reader unfamiliar with the theory
will inevitably be confused. In the mathematical formulas, vectors are never clearly
distinguished as such, and operators and
matrices only occasionally. The lack of
care in the text also appears in statements
that are difficult to understand or even
misleading. On page 30 alone we find that
a summation index is missing from each
of the equations (2.17) to (2.22), a bracket
is missing in the example of butadiene,
and in Equation (2.22) the indices on the
two sides of the equation d o not agree.
Often the symbols in the figures and equations d o not correspond to those in the
text; for example, on pages 32 and 33 the
coefficients are denoted by ‘a’ in the figure
but by a in the text, and on page 95 the
symbol for the basis orbitals is 4 in Equation (6.23) but cp in the text immediately
below. On page 119 the method described
here for minimizing the energy has little to
d o with the Newton-Raphson method to
which the author refers. Also the general
discussion about mathematical methods
C; VCH Verla~gesrllsrhafimbH, D-69451 Weinheim, 1997
for energy minimization is scarcely understandable and will convey little to the
reader. The explanation of CISD in
Section 7.4 is simply incorrect. “CI-singles,doubles” is not, as stated here, a linear combination of the ground state Slater
determinants and the first and second excited states.
There are also many mistakes in the
non-mathematical part of the book. In
Chapter 6 (pericyclic reactions, etc.) even
the first reaction equation (6.1) defining
pericyclic reactions is incorrect. In the
Claisen rearrangement shown here,
allylphenyl ether rearranges to give o-hydroxystyrene. In Equation (6.2) the second reaction arrow has below it nv instead
of hv, and hv is missing from Equation
(6.3). The claim that “. . . no stable ring
systems containing an odd number of
changes in fi can exist . . .” is presumably a guess. Again, it is incorrect
and misleading to state (on page 91) that
for a qualitative treatment of the stereochemistry of photochemical reactions it is
unimportant whether a singlet or a triplet
state is present. The list of errors and examples of slipshod writing could be continued.
The poor quality of the figures is evident even on first opening the book (the
Mobius strip on p. 88 and the energy hypersurface on p. 150 are two interesting
examples). Leaving aside esthetic considerations, many of the figures are not very
suitable for explaining the matters to
which they relate. For example, the connection between the orbital diagram
(6.20) and the reaction equation (6.18)
would only be apparent to a specialist.
Due to the large number of mistakes
and examples of careless writing, the absence of any indications as to the previous
knowledge assumed, and the disjointed
and unclear style in which the arguments
are presented, the reader unfamiliar with
the subject is unlikely to learn much from
the book. Moreover, the price seems unjustifiably high for a textbook of 192
pages. Perhaps the printing error on the
first page-“testbook”
in place of textbook-is
no ordinary mistake but a
Freudian slip.
Raiizer Herges
Institut fur Organische Chemie
der Technischen Universitlt
Braunschweig (Germany)
0570-0833/97/3612-13553 I7.50f .50;0
1355
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