CARBON
NANOSTRUCTURES
5.1. INTRODUCTION
This chapter is concerned with various nanostructures of carbon. A separate chapter
is devoted to carbon because of the important role of carbon bonding in the organic
molecules of life (see Chapter 12), and the unique nature of the carbon bond itself. It
is the diverse nature of this bond that allows carbon to form some of the more
interesting nanostructures, particularly carbon nanotubes. Possibly more than any of
the other nanostructures, these carbon nanotubes have enormous applications
potential which we will discuss in this chapter.
5.2. CARBON MOLECULES
5.2.1. Nature of the Carbon Bond
In order to understand the nature of the carbon bond it is necessary to examine the
electronic structure of the carbon atom. Carbon contains six electrons, which are
distributed over the lowest energy levels of the carbon atom. The structure is
designated as follows ( l ~ ) ~ ,
(2s), (2p,), (2py), (2pJ when bonded to atoms in
molecules. The lowest energy level 1s with the quantum number N = 1 contains two
Introduction to Nanotechnology, by Charles P. Poole Jr. and Frank J. Owens.
ISBN 0-471-07935-9. Copyright 0 2003 John Wiley & Sons, Inc.
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