Silver mirror surface

The system which is the nearest approximation to an ideally flat surface, from which reflection of light is exclusively mirror reflection, is the surface of a silver mirror or of mercury. For that reason, reflection and structural characteristics of a silver mirror surface were firstly examined in order to define the reference standard for the comparison of reflection and structural characteristics of different metal surfaces.7,8 Silver mirror surface is obtained by chemical deposition of silver onto a glass by the silver mirror reaction. 

The opposite case of that of a silver mirror surface are metal coatings obtained from solution without brightening addition agents. These metal surfaces are usually known as mat surfaces. 

The 3D (three-dimensional) STM image (700 x 700) nmofa silver mirror surface is shown in Fig. 2, from which it can be seen that the surface of such a mirror is very smooth. 

The line section analysis of this surface is shown in Fig. 3, which indicates that this surface consisted of relatively flat and mutually parallel parts. The STM software measurements showed that distances between adjacent, relatively flat, parts were several atomic diameters of silver.11 

The line section analysis of a relatively flat part of the surface is shown in Fig. 4. It was shown by STM software data processing that the roughness of the flat part of the surface is less than the atomic diameter of silver, i.e., the flat parts are smooth on the atomic scale. The atomic arrangement of a flat part of a surface is shown in Fig. 5. 

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Figure 2. 3D STM image of a silver mirror surface. Scan size (700 x 700) nm. (Reprinted from Ref.7 with permission from the Serbian Chemical Society.)...

Finally, the reflection of light from the silver mirror surface is mostly mirror reflection which is very close to the ideal reflectance of silver. The structural characteristics of this surface, which enable a high degree of... 

Reflection analysis of a silver mirror surface taken as a reference standard showed that the reflection of light from this surface is mostly mirror reflection and that the degrees of mirror reflection are very close to the ideal reflectance of silver. The structural characteristics of this surface, which provide a high degree of mirror reflection, are flat and mutually parallel parts which are smooth on the atomic level, with adjacent flat parts being separated by several atomic diameters of silver. 

The degrees of development of a surface, determined by the STM analysis as the surface area diff., for the silver mirror surface, the copper surface polished mechanically only and the mirror-bright copper coating obtained from solution Cu II of 25 pm thickness, calculated from an area (880 x 880) nm2, are given in Table 2.12... 

The reflection of light from a silver mirror surface is mostly mirror reflection and the degree of diffuse reflection is very small (up to 2 %). The degree of mirror reflection from this surface is also very close to the ideal reflectance of silver [87,91,92], The silver mirror surface consists of parts parallel to the base and flat on the atomic level with low-step heights between them, as is shown in Fig. 2.28. It is clear that bright metal surfaces must be similar to the surface of the mirror. 

Nikolic ND, Rakocevid Z, Popov KI (2001) The STM analysis of a silver mirror surface. J Serb Chem Soc 66 723-727... 

Each newly cleaved mica surface is very clean. Flowever, it is known that mica has a strong tendency to spontaneously adsorb particles [45] or organic contaminants [46], which may affect subsequent measurements. The mica sheets are cut into 10 nun x 10 nun sized samples using a hot platinum wire, then laid down onto a thick and clean 100 nun x 100 nun mica backing sheet for protection. On the backing sheet, the mica samples can be transferred into a vacuum chamber for themial evaporation of typically 50-55 mn thick silver mirrors. 

Figure 3.1 Schematic diagram of an AAS spectrometer. A is the light source (hollow cathode lamp), B is the beam chopper (see Fig. 3.2), C is the burner, D the monochromator, E the photomultiplier detector, and F the computer for data analysis. In the single beam instrument, the beam from the lamp is modulated by the beam chopper (to reduce noise) and passes directly through the flame (solid light path). In a double beam instrument the beam chopper is angled and the rear surface reflective, so that part of the beam is passed along the reference beam path (dashed line), and is then recombined with the sample beam by a half-silvered mirror.

Lithium containing films were unusual in that the film after curing was damp on the surface with what appeared to be the solvent, DMAC. No other films exhibited this property. The AgNO containing film had the appearance of a silver mirror but the film was exceedingly brittle and "flaky-like". Only two truly flexible films were produced from BTDA + m,m -DABP. These contained Al(acac)3 and NiCl2 6H2O respectively. 

Double-beam atomic absorption instrumentation a = rotating half-silvered mirror b = front surface mirror. 

Aluminum is unique among the metals because it responds to nearly all of the known finishing processes. It can be finished in the softest, most delicate textures as exemplified by tableware and jewelry. Aluminum can be anodized and dyed to appear like gold. It can be made as specular as a silver mirror and jet black. The metal also can be anodized to an extremely hard, wear- and abrasion-resistant surface that approaches the hardness of a diamond. Aluminum is available in many convenient forms-shapes, sheet, plate, ingot, wire, rod and bar, foil, castings, forgings, powdered metals, and extrusions. 

The state-of-the-art mirror system now in use is a glass second-surface silver mirror backed with copper and paint, as shown in Fig. 2. For this system, the characterization and study of the glass/silver, silver/copper, and copper/paint interfaces before and after various stages of use are clearly required to understand the multilayer mirror stack. The methods of characterization outlined in Sec. 2.4 of Ref. 3, especially those of ISS, XPS, AES, and SIMS, are clearly applicable to this problem. In ter facial degradation reactions may begin at the silver/glass interface... 

Fig. 1. Schematic representation of the main features of the interferometric surface forces apparatus. Crossed mica sheets (1) are glued onto semi-cylinder optically polished silica discs (2). One of the discs is attached to a piezoelectric crystal tube (3), and another to the force measuring double cantilever spring (4). White light passes through the window positioned in the bottom of the apparatus and reflects between two silver mirrors. Constructive interference occurs for some wavelengths and the fringes of equal chromatic order are passed through the upper silver mirror to the spectrometer where they can be viewed and their wavelengths determined. Adapted from Ref. [9]. 1996, with permission from Elsevier.

On the basis of reflection and structural analyses of the silver mirror and other different metal surfaces, it can be concluded that the light from flat parts of surface is mirror reflected light. The diffuse reflection arises from the parts of the surface between the flat parts of surface. Flence, these parts of a surface scatter light. 

Hence, the conditions which must be fulfilled in order for metal surfaces to be mirror bright are (i) flat parts of the surface which are smooth on the atomic level and (ii) distances between adjacent flat parts are comparable with the distances between the adjacent flat parts of a silver mirror. 

Surface Silver mirror Copper surface The mirror bright copper coating... 

Fig. 11 On an optical fiber, the cladding is removed along a particular length and AuNPs are immobilized there, right on the waveguide surface, (a) Experimental scheme for a transmission experiment, (b) Experimental scheme for a reflection experiment with a silver mirror at the end face...

Figure 8.11 Silver coatings prepared from PEG 400 (a) silver mirror on inside surface of flask, (b) SEM of silver particles after 3 h and (c) after 8 h, (d) cross-sectional SEM view of film on glass. [Reprinted with permission from Chem. Lett., 2007, 36, 782-783. Copyright 2007 The Chemical Society of Japan.]...

Automatic and quantitative microscopes tend to give erroneous results for transparent particles. To overcome this problem Amor and Block [49] a silver staining technique to make the particles opaque. The particles are dry-mounted on to a thin film of tacky colloidon on a microscope slide. Silver is then deposited from solution using the silver mirror reaction. Preliminary sensitizing the crystalline surface ensures that much more silver is deposited on the particles than on the colloidon. A method of staining particles in aqueous solution prior to deposition on a membrane filter for analysis is also given. 

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