Atomic force microscopy vibrating

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... 

Zhang et al. have recently reported the hydrogenation of SWNTs by H-plasma treatment [17]. The hydrogenation on the surface of SWNTs was confirmed by atomic force microscopy (AFM). Further, the hydrogenation of SWNTs was elucidated by infrared (IR) and Raman spectroscopy measurements. IR spectra showed vibration bands in the range of 2,750-3,000 cm-1 for the hydrogenated SWNTs. 

Monolayers on Air/Solid Interfaces Vibrational Spectroscopy and Atomic Force Microscopy Studies... 

The purpose of this chapter is to demonstrate the usefulness of vibrational spectroscopy [1-8] and atomic force microscopy (AFM) [9,10] in the studies of monolayers on air/solid interfaces. In this chapter, considerable attention is paid to the combined use of vibrational spectroscopy and AFM. These two techniques, widely used in the studies of monolayers on air/solid interfaces, have complementary advantages vibrational spectroscopy is suitable to investigate structure and orientation of monolayers [2,3,6-9], while AFM is useful to observe the surface morphology and the thickness of the monolayers [9]. 

Ceo = Fullerene SWNTs = Single-walled carbon nanotubes MWNTs = Multiwalled carbon nanotubes DWNTs = Double-walled carbon nanotubes CNTs = carbon nanotubes TEM = Transmission electron microscopy HRTEM = High-resolution transmission electron microscopy SEM = Scanning electron microscopy AFM = Atomic force microscopy Ch = Chiral vector CVD = Chemical vapor deposition HiPco process = High-pressure disproportionation of CO RBM = Radical breathing vibration modes DOS = Electronic density of states. 

Mermut, O., Phillips, D.C., York, R.L., McCrea, K.R., Ward, R.S., Somorjai, Ga In situ adsorption studies of a 14-amino acid leucine-lysine peptide onto hydrophobic polystyrene and hydrophilic silica surfaces using quartz crystal microbalance, atomic force microscopy, and sum frequency generation vibrational spectroscopy. J. Am. Chem. Soc. 128, 3598-3607 (2006)... 

Figure 20 shows a typical NSOM. The probe is held at a fixed distance from the specimen by a technique similar to those used in atomic force microscopy. The probe is brought into near contact with the specimen by means of a micropositioner. The probe tip is vibrated parallel to the surface and may be maintained a fixed distance from the surface by using electronic feedback to control the vibration. 

Kim, J., Kim, G., and Cremer, P. S. 2001. Investigations of water structure at the solid/liquid interface in the presence of supported lipid bUayers by vibrational sum frequency spectroscopy. Langmuir 17 7255. Koenig, B. W., Krueger, S., Orts, W. J., Majkrzak, C. F, Berk, N. F., Silverton, J. V., and Gawrisch, K. 1996. Neutron reflectivity and atomic force microscopy studies of a lipid bilayer in water adsorbed to the surface of a silicon single crystal. Langmuir 12 1343. 

In the so-called piezo-mode of atomic force microscopy an ac voltage is applied to a conductive AFM cantilever while scanning the surface of a piezoelectric material. The tip of the cantilever senses the local deformation of the surface caused by the electric field between the tip and a counter electrode (Fig. 5b, see also Fig. 10). Usually the ac frequency is far below the free resonance frequency of the AFM cantilever [16,17,19,20]. In BaTiOs, an image series based on vertical and torsional cantilever vibration signals of the same surface area allowed the reconstruction of the domain orientation using this mode [20]. 

Structural studies of silica sols films were carried out using atomic force microscopy (AFM) method. The films, were prepared by casting solutions on a rapidly spinned substrate - mica. The film surface was scanned at room temperature and atmospheric pressure using a Nanoscope III atomic-force microscope (Digital Instruments, California). Silicon tips with a constant of elasticity of 50 N/m and a tip radius smaller that 10 nm, vibrated at a resonance frequency of about 320 kHz, were used. 

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