Dynamic self-assembly processes

The dynamic self-assembly processes of such supramolecular systems undergoing continous reversible exchange between different self-organized entities in solution may in principle be connected to kinetically controled sol-gel process in order to extract and select an amplified supramolecular device under a specific set of experimental conditions. Such dynamic marriage between supramolecular self-assembly and in sol-gel polymerization processes which synergistically might communicate leads to constitutionnal hybrid materials. ... 

Molecular dynamics simulations are capable of addressing the self-assembly process at a rudimentary, but often impressive, level. These calculations can be used to study the secondary structure (and some tertiary structure) of large complex molecules. Present computers and codes can handle massive calculations but cannot eliminate concerns that boundary conditions may affect the result. Eventually, continued improvements in computer hardware will provide this added capacity in serial computers development of parallel computer codes is likely to accomplish the goal more quickly. In addition, the development of realistic, time-efficient potentials will accelerate the useful application of dynamic simulation to the self-assembly process. In addition, principles are needed to guide the selec-... 

By covalent linkage of different types of molecules it is possible to obtain materials with novel properties that are different from those of the parent compounds. Examples of such materials are block-copolymers, soaps, or lipids which can self-assemble into periodic geometries with long-range order. Due to their amphiphilic character, these molecules tend to micellize and to phase-separate on the nanometer scale. By this self-assembly process the fabrication of new na-noscopic devices is possible, such as the micellization of diblock-co-polymers for the organization of nanometer-sized particles of metals or semiconductors [72 - 74]. The micelle formation is a dynamic process, which depends on a number of factors like solvent, temperature, and concentration. Synthesis of micelles which are independent of all of these factors via appropriately functionalized dendrimers which form unimolecular micelles is a straightforward strategy. In... 

Kay Severin s group has previously investigated the preparation of dynamic combinatorial libraries of metallo-macrocycles for use as sensors for Li+ at physiologically relevant conditions [59]. For example, they have found that ligand 62 and metal complexes 63 undergo a self-assembly process to yield the trimeric complexes depicted in Scheme 4.15 [60]. Mixtures of 64 and... 

Fig. 6 Dynamic combinatorial peptide library that expioits enzyme reactions to control self-assembly processes under thermodynamic controi. (a) Emergence of the potentiai peptide derivatives of varying length in a library of interconverting molecules formed from the staring materials of Fmoc L/L2 system. Fmoc-Ls is preferentially formed. Corresponding AFM images of the fibrillar structures formed at 5 min after the addition of enzyme, and the sheet-like structures observed after 2000 h show that redistribution of the derivatives is accompanied by the remodelling from fibres (Fmoc L3) to sheet-like structures (Fmoc L5). (b) HPLC analysis of the composition of the system reveals the formation and the stabilisation of Fmoc-Ls over time. Modified from [21]...

Dynamic covalent chemistry has been used in an atom-efficient self-assembly process to achieve a nearly quantitative one-pot synthesis of a nanoscale molecular container with an inner cavity of approximately 1.7 nm3. 

Beznosyuk S.A. (2002) Modem quantum theory and computer simulation in nanotechnologies Quantum topology approaches to kinematical and dynamical structures of self-assembling processes, Materials Science Engineering C. 19 (1-2), 369-372. 

Dynamic self-assembly of supramolecular systems prepared under thermodynamic control may in principle be connected to a kinetically controlled sol-gel process in order to extract and select the interpenetrated hybrid networks. Such dynamic convergence between supramolecular self-assembly and inorganic sol— gel processes, which synergistically communicate, leads to higher self-organized hybrid materials with increased micrometric scales. 

While non-covalent bonding interactions may define and direct the self-assembly processes that leads to new supramolecular systems, it is important to note that in general such forces still continue to act once the respective systems are formed. As such, they will continue to govern any dynamic processes that occur within the self-assembled structure. 

The self-assembly process in these studies was driven by strongly interacting groups which bind covalently to the metal surface [159]. However, several protocols for the dynamic formation of SERS hot spots using self-assembly have been developed based on DNA hybridization or n-n interactions [159, 163, 164]. As a result, a wide range of options for the controlled aggregation of silver and gold nanoparticles are now available. 

Chapter 31 - High-temperature quantum chemical molecular dynamics simulations of carbon nanostructure self-assembly processes. Pages 875-889, Stephan Irle, Guishan Zheng, Marcus Elstnerand Keiji Morokuma... 

High-temperature quantum chemical molecular dynamics simulations of carbon nanostructure self-assembly processes... 

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