4.1 Nanocars and the development of molecular manufacturing  (Page 2/7)

Early advances in nanoscale design came in the form of direct demonstration of the movement of single atoms andmolecules with the use of an STM. The first of these demonstrations came in 1989 when IBM fellow Don Eigler spelled out the letters "I BM" on a nickel surface using 35 xenon atoms (figure 2, left). At first glance, the act seemed insignificant, criticized by many as merely astunt. However, at the heart of the demonstration lies the fact that Eigler was able to move single atoms that could not even be observedless than a decade before. This demonstration was a step forward for the development of nanoscale design, and would be followed bysubsequent developments. However, a complication of Eigler’s method was that it required experimental temperatures near absolute zero—anunpractical temperature for the design of useful products.

The second demonstration also came from IBM scientists and overcame the limitations of the previous experiment.In 1996, IBM’s Zurich laboratory produced a nanoscale abacus that consisted of individual C60 molecules that functioned as beads thatcould be pushed back and forth along eleven separate rails on a copper surface (figure 2, right). This time around, the components weremanipulated at room temperature—a practical temperature for the design and application of nanoscale products. This demonstrationrepresented another vital step in the advancement of nanoscale design. It indicated that molecules could be manipulated at roomtemperature and constructed into a functional design—also known as ‘bottom-up’ design.

Molecular building blocks

Since the invention of the STM, the field of molecular manufacturing has produced various molecules that serve as molecular building blocks for more complexly designed moleculesthat are emerging today. The set of building blocks necessary for the development of a design on any scale depends on the targeted functionof that design. For example, in manufacturing an automobile, the necessary materials include bearings, axles, and various othercomponents. The same idea applies to nanoscale design. Depending on the target function of a molecule, it is necessary to use variouscomponents. Here, we take a look at some of the molecular building blocks required to synthesize mobile molecules. Keep in mind thatthese components, and various others, will be used to describe the structure and function of nanocar 1.