Scanning probe microscopy physical chemistry

Hamers RJ (1996) Scanned probed microscopies in chemistry./oMma/ of Physical Chemistry 100 13103-13120. 

Nobel-laureate Richard Feynman once said that the principles of physics do not preclude the possibility of maneuvering things atom by atom (260). Recent developments in the fields of physics, chemistry, and biology (briefly described in the previous sections) bear those words out. The invention and development of scanning probe microscopy has enabled the isolation and manipulation of individual atoms and molecules. Research in protein and nucleic acid stmcture have given rise to powerful tools in the estabUshment of rational synthetic protocols for the production of new medicinal dmgs, sensing elements, catalysts, and electronic materials. 

Appelo CAJ, Postuma D (1993) Geochemistry, groundwater and pollution. Balkema, Rotterdam. Atkins P, de Paula J (2002) Physical chemistry, 7th edn. Oxford University Press, Oxford Bailey GW, AMm LG, Shevcenko SM (2001) Predicting chemical reactivity of humic substances for minerals and xenobiotics Use of computational chemistry, scanning probe microscopy and virtual reality. In Clapp CE et al.. Humic substances and chemical contaminants. Soil Science Society of America, Madison, WI, pp 40-72... 

Around 1980 a new method of microscopy known as scanning probe microscopy (SPM) was invented. Within the past ten years, applications have been increasing exponentially in fields like surface physics and chemistry, biology and optics. SPM is also beginning to emerge as a usefvil and popular technique for R D and quality control in several industries. 

Avouris, Hi., and Lyo, I. W. (1991b). Probing and inducing surface chemistry on the atomic scale using the STM. in Scanned Probe Microscopies, edited by H. K. Wickramasinghe, American Institute of Physics, 1991. 

Scanning Probe Microscopy Group, Department of Electrochemical Mat als, J. Heyrovsky Institute of Physical Chemistry AS CR, v.v.i. Dolejskova 3, 182 23 Prague 8, Czech Republic e-mail pavel.janda jh-inst.cas.cz... 

Electronics electrical engineering physics oj> tical physics atomic physics mathematics statistics imj e analysis materials science photomicrogp aphy interferometry electromagnetics quantum electrodynamics computer science nanotechnology metallography electron microscopy optical microscopy scanning probe microscopy cell biology chemistry. 

Figure 4. Sample scanning probe microscopy images obtained by students in Physical Chemistry Laboratory. (A.) 30 x 30 pm AFM image of the surface of a compact disc. Scale bar = 5 pm, (B.) 3 x 3 nm STM image of highly ordered pyrolytic graphite in constant current mode. Scale bar = 1 nm. (C. and D.) 5x5 pm images of standard copy paper and U. S. currency, respectively. Scale bar = 1 pm. Z-range is 170 nm and 887 nn for (C.) and (D.), respectively.

We first experimented with the Quartz Crystal Microbalance (QCM) in order to measure the ablation rate in 1987 (12). The only technique used before was the stylus profilometer which revealed enough accuracy for etch rate of the order of 0.1 pm, but was unable to probe the region of the ablation threshold where the etch rate is expressed in a few A/pulse. Polymer surfaces are easily damaged by the probe tip and the meaning of these measurements are often questionable. Scanning electron microscopy (21) and more recently interferometry (22) were also used. The principle of the QCM was demonstrated in 1957 by Sauerbrey (22) and the technique was developed in thin film chemistiy. analytical and physical chemistry (24). The equipment used in this work is described in previous publications (25). When connected to an appropriate oscillating circuit, the basic vibration frequency (FQ) of the crystal is 5 MHz. When a film covers one of the electrodes, a negative shift <5F, proportional to its mass, is induced ... 

Modern surface analytical tools make it possible to probe the physical structure as well as the chemical composition and reactivity of interfacial supramolecular assemblies with unprecedented precision and sensitivity. Therefore, Chapter 3 discusses the modern instrumental techniques used to probe the structure and reactivity of interfacial supramolecular assemblies. The discussion here is focused on techniques traditionally applied to the interrogation of interfaces, such as electrochemistry and scanning electron microscopy, as well as various microprobe techniques. In addition, some less common techniques, which will make an increasing contribution to supramolecular interfacial chemistry over the coming years, are considered. 

Giancarlo, L.C. and Flynn, G.W. (1998) Scanning tunnehng and atomic force microscopy probes of self-assembled, physisorbed monolayers Peeking at the Peaks. Annual Review of Physical Chemistry, 49, 297—336. 

Whitworth, A.L., Mandler, D. and Unwin, P.R. (2005) Theory of scanning electrochemical microscopy (SECM) as a probe of surface conductivity. Physical Chemistry Chemical Physics, 7, 356-365. 

Many interesting studies have been published on the effects of a polluted atmosphere on stone with emphasis on the more chemical aspects [39,40,41]. The physical-chemical analytical techniques employed in the study of building materials provide very accurate qualitative and quantitative results on the alterations related to the patina or crust as well as the bulk chemistry of the exposed stone. Scanning electron microscopy (SEM), Electron probe X-ray microanalysis (EPXMA), Fourier-transform infrared analysis (FTIR), X-Ray diffraction (XRD), energy dispersive X-Ray fluorescence, Ion Chromatography, are the most used techniques for the studies of sulphate black crusts as well as to evaluate the effect of exposition time of the sample stone to weathering[42,43]. 

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