Growth forms

By assuming a balhstic delivery of material (e.g., from the vapor phase or through directed evaporation) we obtain at least a qualitative picture for the various growth forms of a faceted crystal surface. We assume that the adsorbed material ( A ) behaves differently from the crystalline substrate ( S ). 

Y. Furukawa, H. Nada. Anisotropic surface melting of an ice crystal and its relationship to growth forms. J Phys Chem B 707 6167, 1997. 

It was found that the region of formation of the chalcogenide halides depends on the pH, the solvent concentration, and the ratios of the initial components in the charge. Temperature and pressure have practically no influence on the phase formation in these systems (285). The use of bromine (283) and SeBr2 as the solvent leads to a different mechanism, having different kinetics of formation and different growth-forms of the crystals (285). 

Plant canopies their growth, form and function. Edited by G. Russell, B. Marshall and P.G. Jarvis... 

Haddow, P.C., Tufte, G., and Van Remortel, P. (2003) Evolving hardware Pumping life into dead silicon. In Kumar, S. and Bentley, PJ. (eds.) On Growth, Form and Computers, Elsevier Academic Press, Amsterdam, pp. 405-423. 

Steps, or growth layers, are structure components for construction of a variety of growth forms in the electrodeposition of metals (e.g., columnar crystals, whiskers, fiber textures). We can distinguish between monoatomic steps, polyatomic microsteps, and polyatomic macrosteps. Only the propagation of polyatomic steps can be observed directly, in situ. 

The dependence of growth forms on overpotentials originates from the potential dependence of nucleation and growth processes. Competition between nucleation... 

Figure 7.18. Current-potential curve showing the correlation between overpotential 17 and growth forms of electrodeposited copper from WCUSO4 and WH2SO4 at 25°C. (From Ref 40, with permission from Elsevier.)...

Structure of the double layer, including concentration of different species present in the solution. The pKJtential dependence of additive adsorption and their effects on growth forms are discussed in Chapter fO. 

Seiter et al. (40) found a correlation between overpotential tj and growth forms of electrodeposited copper on copper sheet substrate with (fOO) texture, shown in Figure 7.18. 

Barnes et al. (44) observed similar results on copper single-crystal surfaces near the (100) face below 10-mV ridges, 40- to 70-mV platelets, 70- to 100-mV blocks, and fine platelets and above 100 mV, polycrystaUine depKJsit. The four basic structural forms are shown in Figure 7.19. Less frequently observed growth forms are p5namids, spirals, whiskers, and dendrites. The structure of depKJsits is discussed further in Chapter 16. 

Figure 1. Calculated growth form of the TPA polymorph 1 crystal, Hartman condition. Kitaigorodsld potential functioiL...

Figure 2. Growth form of a sucrose ciystal (R E) from the Kitaigorodski potential function.

Knight, C.A. Rider, K. (2002). Free-growth forms of tetrahydrofuran clathrate hydrate crystals from the melt plates and needles from a fast-growing vicinal cubic crystal. Philosophical Magazine 82 (8), 1609-1632. 

Based on structural analyses obtained by the electron diffraction technique, the deposited films are known to be monocrystalline in nature, and thus, can be regarded as a special case of a layer-bilayer mechanical growth forming almost two-dimensional crystals. However, there is evidence that Ba-behenate multilayers do in fact show absence of crystallization, as demonstrated by electron micrographic studies. 

The structure of these spherites is uncertain Bradford assumes that they consist of a regular crystalline growth formed by multiple twinning of minute crystals. Scherrer s examination of gold sols, however, has revealed the fact that the crystal interference lines are well developed when the particle contains as few as eighty molecules arranged in the cube lattice, a spherite of OTju. diameter would probably show crystalline properties even if excessive twinning has taken place. 

Givnish, T.J., Leaf mottling relation to growth form and leaf phenology and possible role as camouflage, Eunct. Ecol, 4, 463, 1990. 

We discuss the structural form in Section 4.2 and the equilibrium form in Section 4.3. Section 4.4 presents a summary of the results and investigations of the growth forms. The subject of microtopographs will be discussed in Chapter 5. 

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