Copper surface studies

Z.S. Hu, S.M. Hsu, and P.S. Wang, Tribochemical and thermochemical reactions of stearic acid on copper surfaces studied by infrared microspectroscopy, Tribology Trans., 35, 1, 189-193, 1992. 

With respect to the metal-adsorbate interaction it is of interest, for comparison with the experimental results, to develop theoretical calculations based on molecular models that involve the adsorbate molecules and a metal cluster. The INDO/1 semiempirical method has been proved to be very useful in the stmc-ture optimization and in the evaluation of the bond characteristics throughout the Wiberg index - ° The interaction of azamacrocycle complexes with simulated copper surfaces studied by the same method was performed -... 

E. Vanderiet, J.B.J. Smeets, J.M. Fluit, A. Niehaus, The structure of a clean and oxygen covered copper surface studied by low-eneigy ion-scattering. Surf. Sd. 214(1-2), 111-140 (1989)... 

The study of ultraArin polymer layers on metals is relevairt in understairding Are behaviour of polymers on surfaces, as well as in Are areas of adlresion aird corrosion. Gold aird copper surfaces cair be covered wiAr monolayers of polymers by adsorjrtion from solution [227, 228, 229, 230, 231,232, 233, 234 aird 235]. 

Matsumoto H, Inukai J and Ito M 1994 Structures of copper and halides on Pt(111), Pt(IOO) and Au(111) electrode surfaces studied by in situ scanning tunneling microscopy J. Eiectroanai. Chem. 379 223-31... 

The kinetic study of antioxidant decay by the reaction with hydroperoxides produced by T-6 oxidation proved the catalytic influence of the copper surface. The rate of this reaction in the absence of dioxygen obeys the equation... 

In addition to peroxyl radicals and hydroperoxide, amines are oxidized by dioxygen and this reaction was found to be catalyzed by the copper surface also. This reaction was studied in chlorobenzene and occurs with the rate ... 

Three different subcooled impact conditions under which experiments were conducted and reported in the literature are simulated in this study. They are (1) K-heptane droplets (1.5 mm diameter) impacting on the stainless steel surface with We — 43 (Chandra and Avedisian, 1991), (2) 3.8 mm water droplets impacting on the inconel surface at a velocity of 1 m/s (Chen and Hsu, 1995), and (3) 4.0 mm water droplets impacting on the copper surface with We — 25 (Inada et al., 1985). The simulations are conducted on uniform Cartesian meshes (Ax = Ay — Az — A). The mesh size (resolution) is determined by considering the mesh refinement criterion in Section V.A. The mesh sizes in this study are chosen to provide a resolution of CPR =15. 

Initial studies, described here, involved the use of an ultrahigh vacuum (UHV) surface-analytical instrument coupled to an antechamber. The antechamber allows experiments in solution and electrochemical treatments without transfer of samples outside of the system s controlled atmosphere. Focusing on the chemistry of copper surfaces in aqueous environments suggests the importance of studying the initial stages of surface reactivity with oxygen and water. Electrochemical experiments involve electrolytes thus their surface reactivity should be studied as well. 

Metal ion reduction can also occur during surface studies. One of the best documented examples is that of the reduction of copper(II) to copper(I), a process that has been reviewed extensively in the research literature (11). Certain copper(II) minerals, such as CuO (tenorite), are quite susceptible to photoreduction (11), and care must be taken in conducting surface studies on them. 

In a similar study, Lo et al. have compared the characteristics of atoms sputtered from copper surfaces in simulations which used both pair-additive potentials and EAM potentials Significant differences were found for many... 

These studies were with polycrystalline copper, but more detailed results (Fig. 9) were obtained subsequently (44) with Cu(100), Cu(l 11), and Cu(l 10) surfaces XPS, UPS, LEED, and mass spectrometric data being combined to provide a self-consistent model. The surface species formed with their associated N(ls) and 0(ls) binding energies (eV) on exposing copper surfaces to NO(g) are listed in Table I. 

Azole compounds such as benzotriazole, benzimidazole, indazole and imidazoles are efficient anti-corrosion agents for copper and copper-base alloys [1-10]. Many experimental techniques [11-15] have been used to study the corrosion inhibition mechanisms, however, the mechanisms are still not well understood. It is believed that the complex formation between copper and nitrogen atoms would inhibit oxygen adsorption on copper surface [16-20]. 

Ellis and coworkers studied the effect of lead oxide on the thermal decomposition of ethyl nitrate vapor.P l They proposed that the surface provided by the presence of a small amount of PbO particles could retard the burning rate due to the quenching of radicals. However, the presence of a copper surface accelerates the thermal decomposition of ethyl nitrate, and the rate of the decomposition process is controlled by a reaction step involving the NO2 molecule. Hoare and coworkers studied the inhibitory effect of lead oxide on hydrocarbon oxidation in a vessel coated with a thin fQm of PbO.P l They suggested that the process of aldehyde oxidation by the PbO played an important role. A similar result was found in that lead oxide acts as a powerful inhibitor in suppressing cool flames and low-temperature ignitions.P l... 

The reaction between A-chlorobenzotriazole and l-methyl-2-phenylindole involves formation of the indole radical cation and benzotriazole radical via an initial electron transfer <82JOC4895, 91JCS(P2)1779>. Chemical reactions of benzotriazole on a freshly etched surface of metallic copper are studied by surface-enhanced Raman scattering, x-ray photoelectron spectroscopy, and cyclic voltammetry. The surface product is (benzotriazolato)copper(-l-), which covers the surface in the shape of polymeric material and shows good anticorrosion effects for copper <91JPC7380>. 

As well as presenting a picture of the surface and any molecules on it, STM can also be used to move atoms and molecules across a surface and to make molecules react. If the STM tip is brought closer to the surface than usual, the force between it and atoms/molecules on the surface increases. If this force is attractive, moving the tip across the surface pulls the molecule along after it. A study of 1,4-diiodobenzene on a copper surface at 20 K, for example, demonstrated that the molecule was made to hop along the surface from copper atom to copper atom. Figure 11.13 clearly illustrates that the 1-4, diiodobenzene has moved relative to the CO molecule on the Cu surface. 

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