Chemical Education Today edited by
Book & Media Reviews
Jeffrey Kovac University of Tennessee Knoxville, TN 37996-1600
Nanophysics and Nanotechnology: An Introduction to Modern Concepts in Nanoscience by Edward L. Wolf Wiley-VCH: Weinheim, Germany, 2004. 174 pp. ISBN 3527404074 (paper). $89 reviewed by Frank L. Somer, Jr.
Nanotechnology is clearly one of today’s “hot” topics, in terms of research activity and in the popular literature. A search of available books on the subject will reveal many research-level treatments and non-technical popularizations, but relatively few texts to fill the gap between them. The stated aim of this book is to bridge that gap, serving as an advanced undergraduate-level textbook and as an entry point for workers in related sciences interested in greater involvement in the field. The book grew out of a sequence of two upperlevel physics courses—one devoted to the basic science of nanometer-sized systems and another to the technological applications thereof—taught by the author to students of a variety of majors. This general structure is maintained to some degree, but there is a great deal of integration of principles and applications throughout. An introductory chapter covers some necessary terminology and briefly assesses the current state of nanotechnology and its prospects for future development. The tone of this assessment (that is maintained throughout the book) is fairly conservative, in stark contrast to the many fanciful prognostications found in the popular literature and other media, of which most students will be aware. Many readers might be surprised to learn, for example, that—far from the oft-imagined “self-replicating molecular assemblers”—hardly any micrometer-scale mechanical machines exist at present. That said, the author still conveys a sense of optimism about nanotechnology’s potential, and provides motivation for the rest of the coverage by discussing several real technologies that make use of extremely small structural elements. The most familiar of these is the silicon computer chip, where an exponential decrease in component size with time (Moore’s Law) has enabled a similar increase in computing power. The challenges involved in continuing this trend are a recurring theme throughout the book. The basic-science part of the book begins in earnest with a detailed consideration of how the properties of various simple devices scale with their linear dimension, within the framework of classical physics. Particular cases from the areas of mechanics, heat transfer, and electricity are examined. An interesting example is that used to illustrate the increasing importance of viscous forces on an object moving in a fluid medium as the object’s size becomes small: the author explains that the popular notion that a bumblebee’s flight is
www.JCE.DivCHED.org
•
aerodynamically impossible is true if its wings are considered as airfoils that generate lift according to Bernoulli’s principle, but not if they are considered as oars allowing the bee to row through the relatively immobile (because of the bee’s small size) air. While the reader is assumed to have taken two semesters of calculus-based physics, the discussion of classical mechanics is augmented by a few small tutorials (on Newton’s laws of motion, simple harmonic motion, and coupled harmonic oscillators), set off in shaded sections of text—a useful feature that could probably be used more often than it is through the rest of the text. The focus then shifts to the departures from classical scaling that are encountered as devices approach the nanometer scale. A brief discussion of the discrete nature of matter, light, and electrical charge is followed by several examples of biological systems that serve as models of what is possible in this regime. These include the rotary motors that power microbial flagella, the linear ones that drive muscle contraction, and the ion channels at cell boundaries, which function as nanoscale transistors. Of course, any comprehensive understanding of nanoscale devices will be based largely on the principles of quantum mechanics, the subject of the next two chapters. The first of these covers a fairly standard introductory set of quantum-mechanical models and calculations, and the second is devoted to manifestations of quantum phenomena in the macroscopic world. While these chapters are quite dense and probably not pedagogical enough for students without some fairly substantial previous exposure to quantum mechanics, students who have had such exposure—in a physical chemistry course, for example—will find familiar concepts applied to new and interesting situations: photoexcited electron-hole pairs (“excitons”) in semiconductors, electronic energy levels in quantum dots, and the Casimir force of attraction between reflecting surfaces (which is negligible for macroscopic separations between the surfaces but could be very important in nano-devices), to name a few. The final section of the book considers practical means of assembling nano-structured objects, limitations thereof, and implications for the future. Given the difficulty of manipulating matter on the molecular scale, “self-assembly” (spontaneous formation, given the appropriate ingredients and macroscopically controllable conditions) is an attractive idea for producing such objects, several examples of which (including carbon nanotubes, silver halide crystals used in photographic emulsions, and the magnetite nanocrystals that orient certain bacteria in earth’s magnetic field) are discussed in detail. The two main methodologies that have been used to construct very small objects by direct manipulation of matter—the lithographic techniques used in computer chips and the manipulation of atoms/molecules on surfaces, using STM tips—get a chapter of their own. The discussion here has, understandably, a more engineering feel than the rest of the text, but it is clearly written and contains enough interesting science to hold the attention of chemists. The final
Vol. 82 No. 11 November 2005
•
Journal of Chemical Education
1625
Chemical Education Today
Book & Media Reviews chapter is a philosophical rumination on the future of field, the main thrust of which is to debunk the assumptions underpinning the sorts of doomsday scenarios (such as the famous “gray goo problem”) that can foster a public impression that nanotechnology is an inherently dangerous area of inquiry. This is an interesting and useful book. Its breadth of coverage and extensive list of references will certainly provide scientists in related fields an effective entry point to nanoscience/ nanotechnology. While it is quite dense and sometimes reads more like a review article than a textbook, per se, it could po-
1626
Journal of Chemical Education
•
tentially serve as a textbook for a specialized course taught in a chemistry department at the advanced undergraduate level, most likely with physical chemistry as a prerequisite. It would also be very well suited as an auxiliary text for the quantum mechanics portion of the undergraduate physical chemistry sequence, helping to motivate students by exposing them to cutting-edge applications of principles covered in detail in their main textbook. Frank L. Somer, Jr. is in the Science Department, Columbia College, Columbia, MO 65216;
[email protected] Vol. 82 No. 11 November 2005
•
www.JCE.DivCHED.org
