Imaging Atoms, Molecules, and Chemical Reactions

The laws of chemical combination provided indirect evidence for the existence of atoms. The experiments of Thomson, Wien, and Rutherford provided direct physical evidence for the existence of the elementary particles that make up the atom. We conclude this chapter by describing an experimental method that allows us not only to image individual atoms and molecules but also to observe and control a chemical reaction at the single molecule level—a feat only dreamed of as recently as the mid-1980s. 

Institut FOr AllgemeinePhysik, Technical University, Vienna, Austria b courtesy of Dr. Don Eigler/IBM Almaden Research Center, San Jose, CA 

Imaging and Controlling Reactions at the Single Molecule Level Using the Scanning Tunneling Microscope 

The STM has been used to image the surfaces of materials since the mid-1980s, but only recently has it been used to image single molecules and initiate chemical reactions at the single molecule level, as we illustrate with the following 

Matter can be classified systematically by its uniformity and its response to a variety of separation processes compounds and elements are the basic chemical building blocks. 

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