Electron tunneling microscopes

Figure 2.1 Atoms can be seen as humps on the surface of a solid using the electron tunnelling microscope...

Other methods include the use o X ray crystallography (known for many years) to identify crystalline molecules. When X-rays interact with a molecule with a distinct crystal structure, the resulting X-ray scattering patterns can often be analyzed to provide clues to its chemical structure. With modern computer technology, a picture of the structural features of a molecule can be produced and the methodology has been expanded to include structures of proteins and even biologically active small molecules docked to a protein. With modern electron tunneling microscopes, pictures of atoms have been made. 

Theoretical reactions at electrodes as well as between redox couples in solutions can be interpreted in terms of electron tunneling. Microscopic aspects of the charge transfer in the phenomenological treatment are contained in the rate constants k and the transfer coefficient a. 

Marrian C R K, Perkins F K, Brandow S L, Koloski T S, Dobisz E A and Calvert J M 1994 Low voltage electron beam lithography in self-assembled ultrathin films with the scanning tunneling microscope Appi. Rhys. Lett. 64 390... 

Electrons from a scanning tunneling microscope (STM) in ultrahigh vacuum have been used to create surface-isolated silyl radicals on Si(lll), and their exposure to styrene leads to the formation of compact islands containing multiple... 

The basis of the scanning tunnelling microscope, illustrated schematically in Figure 3.5, lies in the ability of electronic wavefunctions to penetrate a potential barrier which classically would be forbidden. Instead of ending abruptly at a... 

Our laboratories are currently equipped with three UHV Omicron microscopes, a variable-temperature scanning tunneling microscope (STM), a room-temperature atomic force microscope (AFM)/STM, and a low-temperature liquid helium bath cryostat STM, all of which are currently driven by Omicron Scala software and electronics. 

The nanoscale world is exciting because it is governed by rules differing from those in the macroscopic, or even microscopic, realm. It is a world where quantum mechanics dominates the scene, and events on the single-molecule scale are critical. What we know about the behavior of material on our scale is no longer true on the nanometer scale, and our formularies must be re-written. In order to study this quantum world, a quantum-mechanical probe is essential. Electron tunneling provides that quantum-mechanical tool. 

Schmickler W, Tao N (1997) Measuring the inverted region of an electron transfer reaction with a scanning tunneling microscope. Electrochim Acta 42 2809-2815... 

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