Surface Structure Analysis

Takayanagi K 1990 Surface structure analysis by transmission electron diffraction—effects of the phases of structure factors Acta. Crystalloger A 46 83-6... 

The major role of TOF-SARS and SARIS is as surface structure analysis teclmiques which are capable of probing the positions of all elements with an accuracy of <0.1 A. They are sensitive to short-range order, i.e. individual interatomic spacings that are <10 A. They provide a direct measure of the interatomic distances in the first and subsurface layers and a measure of surface periodicity in real space. One of its most important applications is the direct determination of hydrogen adsorption sites by recoiling spectrometry [12, 4T ]. Most other surface structure teclmiques do not detect hydrogen, with the possible exception of He atom scattering and vibrational spectroscopy. 

Marchut L, Buck T M, Wheatley G H and McMahon C J Jr 1984 Surface structure analysis using low energy ion scattering Surf. Sc/. 141 549-66... 

ReflEXAES can be used for near-surface structural analysis of a wide variety of samples for which no other technique is appropriate. As with EXAES, ReflEXAES is particularly suited for studying the local atomic structure around particular atomic species in non-crystalline environments. It is, however, also widely used for the analysis of nanocrystalline materials and for studying the initial stages of crystallization at surfaces or interfaces. ReflEXAES was first proposed by Barchewitz [4.135], and after several papers in the early nineteen-eighties [4.136, 4.168-4.170] it became an established (although rather exotic) characterization technique. Most synchrotron radiation sources now have beam-lines dedicated to ReflEXAES experiments. 

Somorjai GA. 1992. The frontiers of surface-structure analysis. Surf Interface Anal 19 493-507. 

Zeth, K., Offermann, S., Essen, L.-O., and Oesterhelt, D. 2004. Iron-oxo clusters biomineralizing on protein surfaces structural analysis of Halobacterium salinarum DpsA in its low- and high-iron states. Proceedings of the National Academy of Sciences of the USA 101 13780-13785. 

Lapujoulade, J., Salanon, B., and Gorse, D. (1984). Surface structure analysis by atomic beam diffraction. In The Structure of Surfaces, edited by Van Hove, M. A., and Tong, S. Y., Springer-Verlag, Berlin. 

The basic complication of surface structure analysis by LEED comes from the fact that observation of the diffraction pattern geometry serves only to determine the size and shape of the two-dimensional unit cell, which... 

THE THEORY OF MODERN TECHNIQUES FOR SURFACE STRUCTURE ANALYSIS... 

Time resolved surface structure analysis can be employed for studies of order-order and order-disorder surface phase transitions, growth, and evaporation. Surface structures and their alterations could then be explored under extreme conditions of high temperature and irradiation by photons or particles. 

The two isocyanate groups of BICDPM react with amino groups of the PVFA-co-PVAm chains as well as with silanol groups of the silica surface. Structure analysis of PVFA-co-PVAm/silica particles cross-linked with BICDPM was carried out by means of solid state 13C CPMAS NMR spectroscopy (Fig. 6) and XPS (Fig. 2b). 

J2.20 Ligands on clusters - adsorbates on surfaces J2.21 Monolayer surface structure analysis... 

Among the spectroscopic (EXAFS-like) methods of analysis of local atonuc structure, the SEFS method is a purely surface technique. The analyzed-layer depth in the SEFS method is determined by the mean free path of the secondary electrons and amounts to about 5-7 A. It is not feasible to obtain such a small depth of the analyzed layer by other EXAFS-like methods of surface structure analysis. It should be mentioned that from the standpoint of the physics of surfaces, information on the atonuc structure of superthin surface layers is of most interest, since it is precisely in these surface layers that one encounters the most considerable changes due to the presence of a free surface in a solid. The use of electron optics in the SEFS method makes it possible to obtain extrahigh resolution for the analyzed area (down to several nanometers), which presently is not attainable with X-ray optics used in the EXAFS method. 

Three-Dimensional Surface Structure Analysis of the Nucleus... 

Fuji, M., Ueno, S., Takei, T., Watanabe, T. and Chikazawa, M. (2000). Surface structural analysis of fine silica powder modified with butyl alcohol. Colloid Polym. Sci., 278, 30-36. 

Shadowing and blocking using MEIS can be applied if the adsorbate gives rise to a significant blocking dip, i.e., if the atomic number is not very small and the thermal vibrations are not too large. A full surface-structure analysis must then be undertaken to incorporate a possible adsorption-induced relaxation. 

The application of LEED is limited to ultrahigh vacuum (UHV) conditions because of the character of the probe and its high surface sensitivity. The main application is the study of single crystal metal and semiconductor surfaces, and adsorption on these surfaces. Study of surfaces of thin insulator films is also possible. Recently, the application extends to study the surface structure of quasicrystals. LEED is widely applied to determine the symmetry and periodicity of surface structures and thus to identify reconstructions and adsorbate phases by observing the diffraction pattern. It is also a technique for quantitative surface structure analysis. LEED is also appHed as the quantitative determination of thermal vibrations at surfaces. 

Comparison with Other Reiated Surface Structure Analysis Techniques... 

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