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Oxford University Press: New York,
1997. 303+ pp. ISBN 0-19-509549-9. $29.95.
Modern publishers prefer to direct books toward
specific target markets, and this book is said to be aimed at
the undergraduate senior or beginning graduate student
special topics course on hydrogen bonding. Whether there really
are many such courses and whether this book would serve as
a textbook is debatable. On the other hand, it will be a
valuable reference for all chemists interested in hydrogen bonding
in structural chemistry, supermolecular chemistry,
and biomolecular recognition. It has long been a tradition
in scholarship for a master to put together a general
treatment of the topic that was the focus of his or her career. An
understanding of the special relationships among otherwise
diverse observations becomes apparent only through prolonged
attention and it is good to pass this perspective to future
scholars. What better reason can a book have for its existence?
The book begins with a brief (too brief?)
historical perspective on hydrogen bonding. This is followed by a
chapter describing various modern theoretical descriptions of
hydrogen bonds, including the Morokuma decomposition of
H-bond energies into contributing attractive and repulsive terms
and descriptions of H-bond potential energy diagrams. The
subsequent three chapters on strong, moderate, and weak
hydrogen bonds are illustrated with example structures ranging
from the hydrogen bifluoride ion to acetylene p interactions.
There are five chapters covering special topics including
water hydrates, clathrates, hydrogen bonding in biomolecules,
and finally a chapter giving a brief description of physical
and calculational methods for studying hydrogen bonding.
But this book is not organized as a traditional textbook
with general principles pronounced prominently, followed by
more complex details and sophisticated applications to
illustrate these general principles. In this book the reader is
expected to extract general principles from the detailed
experimental results given in a vast number of tables and figures.
The author has collected and compared data from hundreds
of experiments with only minimal verbal exposition. The
book strongly reflects the diffractionist's background of the
author; there are dozens of tables of distances and angles
derived from X-ray or neutron diffraction data. To make the
point that maximal H-bonding need not require a 180° angle
for O-H...O, Jeffrey gives a distribution plot of angle vs
H...O distance for various carbohydrate systems. The comparison
of scatterplots of O-H...O angles vs H...O distances or of the
same angles vs O-to-O distances for carbohydrates show that
the latter parameter is relatively insensitive to angle or
hydrogen bond distance. Students using this as a textbook may be
put off by this reliance on tabular and graphics information
and the lack of written comments. Their frustration would
be further kindled when important concepts are left
undefined and methods unexplained. As examples, the
conic-correction factor for bond angles in crystal structures is mentioned
at least twice but never explained; type I and II clathrate
hydrates are described in a table but never defined in words.
Many tables and figures require more explanation than is given
either in the legend or the text. There are also some
incorrectly drawn structural formulas, especially in Chapter 3.
For the more sophisticated reader this abundance of
tables and figures is a virtue. There is nowhere else one can go
for such a wealth of information and a comparison of the
hydrogen bonding features of such a wide variety of
compounds. The focus is on the recent literature, with more than 750
references covering up to 1995, and the experienced reader
can go to that literature for expanded descriptions.
Contemporary controversies such as "the presence or absence of
C-H...B bonds" or "the structure of water" are handled impartially
but with Jeffrey's special take on such topics. For example, he
raises the question whether shorter C-H...B contacts in
crystals should be taken as evidence of special attractive forces, an
unconventional thought to most structural chemists. Such
contacts may actually be forced contacts because in the
Morokuma description of hydrogen bonds the repulsive exchange
term dominates at closer distances over the attractive
electrostatic forces. Jeffrey has been involved with such structures since
the 1950s and he provides an excellent overview of this
interesting and practically important topic. The chapter on
hydrogen bonding in biological molecules is the best place for
a biochemistry graduate student to begin to learn more than
is given in standard physical and organic chemistry
textbooks. The book is dedicated to Linus Pauling and frequent
footnotes give interesting anecdotes acknowledging the
seminal work of Pauling in many topics covered in this book.
In summary, I would not select this as a required
textbook for my class on biomolecular structure, but I would put a
copy on reserve and I would dig deep into this mine of
information to illustrate many a lecture point. It is a valuable addition
to any chemist's library.
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