2D self-assembly

D self-assembly of metal nanoparticles requires special conditions since 3D growth of any kind of material is preferred. Two principal strategies to generate 2D organizations of metal nanoparticles have been developed during the last 1-2 decades true self-assembly, guided self-assembly and aimed structures. 

Keywords 2D self-assembly Chiral surfaces Crystallization Enantiomorphism Molecular monolayers... 

Investigating 2D self-assembly at the molecular level provides new insight into complex inter molecular interactions. These model studies are usually performed under well-defined conditions in order to have more control on complicated surface processes [13]. This includes single-crystal substrates which allow the application of diffraction techniques. 

Fig. 9 Assembly of DNA junctions, a Four of the junctions in motif 2 are complexed to yield the structure in motif 5. The complex has maintained open valences so that it could be extended by the addition of more monomers, b Square lattice formed from four-arm junctions held in a square-planar configuration (6) by protein RuvA, with TEM image of the lattice shown beneath. The scale bar represents 100 nm. Reprinted with permission from [47], c ID self-assembly of the motif 7 derives into a railroad track-like array 8, and the 2D self-assembly produces a lattice array 9. An AFM image of array 9 is shown beneath with a scan size of 400 x 400 nm2. Adapted with permission from [45,46]...

Surface plasmon resonance (SPR) absorbance of 2D self-assembled silver nanosphere arrays has been theoretically examined regarding its size/concentration dependence. The simple and accurate fitting formula for SPR wavelength has been derived. Optical diagnostics for 2D nanoarrays with high density of noble-metal nanoparticles is proposed. 

We analyzed the relation between absorbance spectrum of 2D self-assembled silver nanoparticle arrays and size and concentration of the nanoparticles. The high sensitivity of these parameters can be the basis for proper characterization of close-packed metal nanoparticle structures. For express optical diagnostics we provided the simple approximation for dependence of the resonance wavelength on size and surface concentration of nanoparticles. 

Scheme 17 Primary halogen-bond motif causing a 2D self-assembled structure. ...

Kreher D, Colas A, Mathevet E, Jean A (2013) Steered 2D.self-assembly of 3D Janus tectons equipped with photoswitchable chromophores. In ref. [18], 335... 

The advantages of lithographic methods are good size controllability and structural uniformity. However, since these methods rely on 2D self-assembling array structures, the enhancements are limited only on surfaces. It is therefore impossible to observe a sample in a bulk matrix or in a solution. Though the number of studies remains limited, wet chemical synthesis of Al and indium nanocrystals has been reported [22-26]. Al nanocrystals 50-100 nm in size have been successfully fabricated using alane derivatives as precursors and molecules with one or a pair of... 

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