Self-assembly growth stages

Scheme I illustrates the self-assembly growth of zinc-bisquinoline from 8,8 -dihydroxy-5,5 -biquinoline (bisquinoline). The reaction of bisquinoline with Zn(Et)2 is almost instantaneous. Figure 1 illustrates the ellipsometrically determined film thicknesses as a function of dip cycle. The two markedly different regimes (Stage I and Stage II) with growth rates of 8.3 and 26.5 A/dip cycle (d.c.) respectively, indicate a complex film growth. Films thicker than 250 A maintain the 26.5 A/d.c. growth rate as far as we have measured (c.a. 1,275 A).

At this stage, we could also address the question of nucleation and growth processes involved in these self-assembly reactions. In some cases, the molecular structures display a planar or a rhomb-like arrangement of the coordination polyhedra, like for [Mo204(OMe)6 Mn(CO)3 2], [Mo206(OMe)4 Ru(p-cymene)2] and... 

Since the first observation of the formation of defect-free three-dimensional (3D) islands in the early stage of germanium deposition on silicon, the growth of Ge/Si self-assembled quantum dots has attracted a considerable interest [1]. The carrier localization, the three-dimensional confinement, the high Ge content achieved with the heterostructures represent specific advantages for a new generation of devices... 

For this reason, microfluidic channels are usually designed with width of 100 pm or less, representing an efficient reactor for rapid mixing of fluids, transforming the stages of carrier fabrication into a self-assembly (nucleation, growth by aggregation, and stabilization after a characteristic time scale) in a well-controlled automatic process. 

Growth stages in the S-layer (S. ureae ATCC 13881) self-assembly process. 

Self-assembly The generation of a well-defined supermolecule from a given set of components, under appropriate conditions. The process involves three stages recognition between the components appropriate orientation of the components to allow growth of the structure termination of the growth to give a finite supramolecular species. The term also applies to the formation of supramolecular assemblies from their components. 

Cobalt nanodisks have also been prepared by the same method and the same precursor in the presence of rhodamine (RhB) and HDA. The bulkiness of RhB, which hinders its adsorption on the Co surface in the early growth stages as well as the specific adsorption of HDA at the 0001 facets, is responsible for this peculiar growth mode. An out-of-plane magnetization was observed. These nano-objects self-assemble into ID chains with high magnetic anisotropy [59]. 

In the early stages of planning the book the tentative title Supramolecular Polymerizations was adopted. It was thus intended to restrict the content of the book to the new class of self-assembled polymers that undergo reversible growth by the formation of noncovalent bonds. This class (Part II) is wider than expected not only mainchain assemblies of hydrogen-bonded repeating units, but also planar organization of S-layer proteins, micellar and related three-dimensional structures of block copolymers may be described as a result of supramolecular polymerization. 

---