Scanning tunneling microscopy generally

We have considered briefly the important macroscopic description of a solid adsorbent, namely, its speciflc surface area, its possible fractal nature, and if porous, its pore size distribution. In addition, it is important to know as much as possible about the microscopic structure of the surface, and contemporary surface spectroscopic and diffraction techniques, discussed in Chapter VIII, provide a good deal of such information (see also Refs. 55 and 56 for short general reviews, and the monograph by Somoijai [57]). Scanning tunneling microscopy (STM) and atomic force microscopy (AFT) are now widely used to obtain the structure of surfaces and of adsorbed layers on a molecular scale (see Chapter VIII, Section XVIII-2B, and Ref. 58). On a less informative and more statistical basis are site energy distributions (Section XVII-14) there is also the somewhat laige-scale type of structure due to surface imperfections and dislocations (Section VII-4D and Fig. XVIII-14). 

As mentioned above, the methods based on detection of electrons or ions or probing the electrode surface by these particles are generally handicapped by the necessity to move the studied electrode into vacuum, i.e. to work ex-situ. There are, however, two important exceptions to this rule electrochemical mass spectrometry and electrochemical scanning tunnelling microscopy. 

H.-J. Guntherodt and R. Wiesendanger (eds) Scanning Tunneling Microscopy I General Principles and Applications to Clean and Adsorbate-Covered Surfaces, Springer, Berlin, 1992. 

Sacks, W., and Noguera, C. (1991). General expression for the tuimeling current in scanning tunneling microscopy. Phys. Rev. B 43, 11612-11622. 

The oldest microscopy technique for materials analysis was optical microscopy. Even to this day, for feature sizes above 1 pm, this is one of the most popular tools. For smaller features, electron microscopy techniques such as scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are the tools of choice. A third family of microscopy includes scanning probe tools such as scanning tunneling microscopy (STM) and atomic force microscopy (AFM). In these relatively recent techniques, sample preparation concerns are of minor importance compared to other problems, such as vibration isolation and processing of atomically sharp probes. Therefore, the latter techniques are not discussed here. This chapter is aimed at introducing the user to general specimen preparation steps involved in optical and electron microscopy [3 7], which to date are the most common... 

There exists a large number of literature on SAM formation and characterization in general [1,3-5] and on functionalized alkane thiols in particular [6-8], The most frequently used methods to analyze the SAMs are Scanning Tunneling Microscopy (STM), Infra-red spectroscopy (IRS), X-ray absorption spectroscopy (NEXAFS) and Low Energy Electron Diffraction (LEED). In this contribution we will focus on the application of Thermal Desorption Spectroscopy (TDS). This method allows... 

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