Zinc single crystal

The adsorption of some neutral organic compounds on the individual faces of zinc single-crystal electrodes was described by the Frumkin-Damaskin theory with the use of two parallel capacitors model [14]. For pc-Zn electrode, a departure from the two parallel capacitors model due to the energetic inhomogeneity of the surface was observed. 

Fig. 12. Dependence of zinc single-crystal fracture strain on temperature and environment (a) air,(b) mercury (after Rozhanskii et al. - ref. 15)...

Most investigations on edl of zinc single-crystal faces were made in solutions containing organic compounds tetraethy-lammonium cations [7], hexanol [17-19], tetrabutylammonium cations [13, 14, 18, 19], camphor [18-20], cyclohexanol [14, 21], andTU [22, 23[. For these substances, dependence of adsorption properties on... 

Fig. IX-33. Stretching load, P, as a function of the degree of deformation, e (%), of zinc single crystal clean and in the presence of liquid mercury...

Shchukin, E. D. and V. I. Lichtman. 1959. On brittle fracture of zinc single crystals. Doklady AN SSSR. 124 307-310. 

FIGURE 7.4 Stress, P strain, e curves for a pure zinc single crystal and a zinc single crystal covered with mercury film. (From Rehbinder, P.A. and Shchukin, E.D., Surface phenomena in solids during deformation and fracture processes, in Progress in Surface Science, S.G. Davison (Ed.), Pergamon Press, Oxford, U.K., 1972, pp. 97-188 Shchukin, E.D. and Lichtman, V.I., Doklady AN SSSR., 124, 307, 1959.)... 

These expressions indeed hold true for the fracture of zinc single crystals having different orientations in the case of both brittleness caused by the presence of active liquid metal (mercury or gallium) and brittleness caused by a temperature change, that is, low-temperature brittleness (Figure 7.21). This opens the opportunity for a comparison of the surface energy values in the first case, the value of K is 2-2.5 times smaller than in the second case, which, in turn, corresponds to approximately fivefold lowering of o upon contact with a liquid metal. 

FIGURE 7.23 Temperature dependence of plasticity (crystallographic yield stress), (a), and of the strength, K = (b), for zinc single crystals—uncoated and coated with mercury. (From Rehbinder, P.A. and... 

Figure 7.9 Slip in a zinc single crystal. (From C. F. Elam, The Distortion of Metal Crystals, Oxford University Press, London, 1935.)...

Rehbinder and co-workers were pioneers in the study of environmental effects on the strength of solids [144], As discussed by Frumkin and others [143-145], the measured hardness of a metal immersed in an electrolyte solution varies with applied potential in the manner of an electrocapillary curve (see Section V-7). A dramatic demonstration of this so-called Rehbinder effect is the easy deformation of single crystals of tin and of zinc if the surface is coated with an oleic acid monolayer [144]. 

The rate (or kinetics) and form of a corrosion reaction will be affected by a variety of factors associated with the metal and the metal surface (which can range from a planar outer surface to the surface within pits or fine cracks), and the environment. Thus heterogeneities in a metal (see Section 1.3) may have a marked effect on the kinetics of a reaction without affecting the thermodynamics of the system there is no reason to believe that a perfect single crystal of pure zinc completely free from lattic defects (a hypothetical concept) would not corrode when immersed in hydrochloric acid, but it would probably corrode at a significantly slower rate than polycrystalline pure zinc, although there is no thermodynamic difference between these two forms of zinc. Furthermore, although heavy metal impurities in zinc will affect the rate of reaction they cannot alter the final position of equilibrium. 

FIGURE 11.16 (a) A saturated solution of zinc acetate in water, (b) When additional acetate ions are added (as a single crystal of solid sodium acetate in the spatula shown in part (a)), the solubility ot the zinc acetate is significantly reduced and more zinc acetate precipitates. 

Infrared optics is a fast growing area in which CVD plays a maj or role, particularly in the manufacture of optical IR windows. 1 The earths atmosphere absorbs much of the infrared radiation but possesses three important bandpasses (wavelengths where the transmission is high) at 1-3 im, 3-5 im and 8-17 pm. As shown in Table 16.2, only three materials can transmit in all these three bandpasses single crystal diamond, germanium, and zinc selenide. 

Solid-state, esr spectra of [Cu(Et2dtc)] and [Cu S2P(OPr )2 2] dissolved in coordinating and noncoordinating solvents have been compared with single-crystal and powdered samples diluted with the corresponding complexes of divalent nickel and zinc. With noncoordinating... 

Zinc sulfide, with its wide band gap of 3.66 eV, has been considered as an excellent electroluminescent (EL) material. The electroluminescence of ZnS has been used as a probe for unraveling the energetics at the ZnS/electrolyte interface and for possible application to display devices. Fan and Bard [127] examined the effect of temperature on EL of Al-doped self-activated ZnS single crystals in a persulfate-butyronitrile solution, as well as the time-resolved photoluminescence (PL) of the compound. Further [128], they investigated the PL and EL from single-crystal Mn-doped ZnS (ZnS Mn) centered at 580 nm. The PL was quenched by surface modification with U-treated poly(vinylferrocene). The effect of pH and temperature on the EL of ZnS Mn in aqueous and butyronitrile solutions upon reduction of per-oxydisulfate ion was also studied. EL of polycrystalline chemical vapor deposited (CVD) ZnS doped with Al, Cu-Al, and Mn was also observed with peaks at 430, 475, and 565 nm, respectively. High EL efficiency, comparable to that of singlecrystal ZnS, was found for the doped CVD polycrystalline ZnS. In all cases, the EL efficiency was about 0.2-0.3%. 

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