Surface topology

Yuan J-Y, Shao Z and Gao C 1991 Alternative method of imaging surface topologies of nonconducting bulk specimens by scanning tunnelling microscopy Phys. Rev. Lett. 67 863... 

Opt. Eng. 18, 125, 1979. This article presents an analysis of the relation between angle-resolved light scattering and surface topology. 

The chemical nature of the packing has the largest influence on the retention of molecules and a big impact on the efficiency of the separation itself. The chemical and physical properties of the sorbent are determined by the choice of the comonomers for the copolymerization. The type of the copolymerization process employed by the synthetic chemist introduces the macroporous structure into the sorbent and determines the surface topology (accessibility, resolution) and the surface chemistry of the packing (4). 

Topography - surface topology, watercourses, surrounding property, vegetation, access ... 

Ammonia activation by Pt, to be discussed in the next section, is an interesting example, because it illustrates the basic principle that provides chemical direction to the identification of surface topologies that give low reaction barriers in surface reactions. This holds specifically for elementary reactions that require a surface ensemble of atoms. 

We now proceed to look at three examples from recent work in some depth. In the first example, we wish to illustrate that a knowledge of the VB structure or of the states involved in photophysics and photochemistry rationalize the potential surface topology in an intuitively appealing way. We then proceed to look at an example where the extended hyperline concept has interesting mechanistic implications. Finally, we shall look at an example of how conical intersections can control electron transfer problems. 

In Figure 9.29, we show three surface topologies that we have been able to document in electron transfer processes in radical cations. Two views are presented in each case. At the top, we show a cross-section along the coordinate orthogonal to the reaction path (analogous to that shown for X2 in Fig. 9.28a). Then, at the bottom, we... 

Figure 9.29. Three conical intersection surface topologies for electron transfer processes in radical cations (adapted from reference 5).

Bernardi F, Olivucci M, Robb MA (1990) Predicting forbidden and allowed cycloaddition reactions potential surface topology and its rationalization. Acc Chem Res 23 405... 

In what follows we will discuss systems with internal surfaces, ordered surfaces, topological transformations, and dynamical scaling. In Section II we shall show specific examples of mesoscopic systems with special attention devoted to the surfaces in the system—that is, periodic surfaces in surfactant systems, periodic surfaces in diblock copolymers, bicontinuous disordered interfaces in spinodally decomposing blends, ordered charge density wave patterns in electron liquids, and dissipative structures in reaction-diffusion systems. In Section III we will present the detailed theory of morphological measures the Euler characteristic, the Gaussian and mean curvatures, and so on. In fact, Sections II and III can be read independently because Section II shows specific models while Section III is devoted to the numerical and analytical computations of the surface characteristics. In a sense, Section III is robust that is, the methods presented in Section III apply to a variety of systems, not only the systems shown as examples in Section II. Brief conclusions are presented in Section IV. 

Mardilovich, I.P., E. Engwall, and Y.H. Ma, Dependence of hydrogen flux on the pore size and plating surface topology of asymmetric Pd-porous stainless steel membranes, Desalination, 144, 85-89,2002. 

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