Crystal engineering self-assembly

We also want to inspire all scientists in the fields of supramolecular chemistry , crystal engineering , self assembly and nanoscience to explore and use these concepts and ideas in their work. 

With the recognition that many substances may cocrystallize in a single continuous lattice structure, scientists have more recently initiated intense studies of the mixed molecular crystal systems that have become known as cocrystals [10]. This particular area of solid-state research has led pharmaceutical scientists into the areas of crystal engineering and assembly of appropriate supramolecular synthons, with particular emphasis on understanding the origins of the molecular self-assembly that takes place in the formation of cocrystal systems. 

The importance of surface characterization in molecular architecture chemistry and engineering is obvious. Solid surfaces are becoming essential building blocks for constructing molecular architectures, as demonstrated in self-assembled monolayer formation [6] and alternate layer-by-layer adsorption [7]. Surface-induced structuring of liqnids is also well-known [8,9], which has implications for micro- and nano-technologies (i.e., liqnid crystal displays and micromachines). The virtue of the force measurement has been demonstrated, for example, in our report on novel molecular architectures (alcohol clusters) at solid-liquid interfaces [10]. 

VI. PREDESIGNED THREE-DIMENSIONAL SELF-ASSEMBLY OF PROTEINS CRYSTAL ENGINEERING ... 

Fig. 4.5 Optical photograph of the composite colloidal crystal array film self assembled on a Teflon film. The submicron particles were composed of 326 nm diameter polystyrene beads coated with a 20 nm thick Si02 shell. Reprinted from Ref. 15 with permission. 2008 Institute of Electrical and Electronics Engineers...

The exploitation of the reactivity of molecular crystals lies close to the origins of crystal engineering and is at the heart of the pioneering work of Schmidt [47a]. The idea is that of organizing molecules in the solid state using the principles of molecular recognition and self-assembly. Successful results have been obtained with bimolecular reactions, particularly [2+2] photoreactivity and cyclisation [47b,c]. Another important area is that of host-guest chemistry. 

It is obvious that these molecular systems can be prepared specially or can form spontaneously as self-assemblies when hydrogen or dihydrogen bonds dictate the processes of molecular aggregation. The latter is particularly importaut in supramolecular chemistry and crystal engineering, where the primary attention is focused on mastering weak intermolecular interactions [1]. 

Aoyama, Y. Endo, K. Anzai, T. Yamaguchi, Y. Sawaki, T. Kobayashi, K. Kane-hisa, N. Hashimoto, H. Kai, Y. Masuda, Y. Crystal Engineering of Stacked Aromatic Columns. Three-Dimensional Control of the Alignment of Orthogonal Aromatic Triads and Guest Quinones via Self-Assembly of Hydrogen-Bonded Networks. J. Am. Chem. Soc. 1996, 118, 5562-5571. 

Therefore, (nonlinear) photonic crystal properties can be attributed to purple membrane patches of bacteriorhodopsin. This is an important finding, since this natural material exhibits photonic bandgap properties without careful and costly engineering, but through self-assembly. In... 

Diamondoid networks represent just one example of the types of architecture that can be generated in a rational manner using the modular self-assembly approach. The remainder of this chapter will focus upon the diversity of simple architectures that are accessible using crystal engineering strategies, many of which have no precedent in minerals yet are afforded via one-pot reactions and commercially available components. 

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