Mesoscopic material

The term nanosized cluster or nanocluster or simply cluster is used presently to denote a particle of any kind of matter, the size of which is greater than that of a typical molecule, but is too small to exhibit characteristic bulk properties. Such particles enter the size regime of mesoscopic materials. 

MODERN APPROACHES IN POINT-CONTACT SPECTROSCOPY AND THEIR APPLICATION TO PROBE NANOCLUSTERS IN MESOSCOPIC MATERIALS... 

Contemporary research trends related to the development of mesoscopic materials, which contain nanosized inclusions of guest compounds and phases in a host matrix, are among the most prospective fields for technological applications. The physical characteristics of nanoobjects in such materials can substantially differ from those of their macroscopic analogs. As a result there is a strong need to investigate both the properties of individual nano-objects and their parameter modifications when they interact with their environment. 

Nanocomposites or mesoscopic materials are of interest in many fields of materials science, solid-state physics and solid-state chemistry. This is also true in the research of magnets much effort has been spent on these kind of materials. The most recent development is that of exchange-coupled magnets, in which hard and soft magnetic fine... 

Mesoscopic materials form the subset of nanostructured materials for which the nanoscopic scale is large compared with the elementary constituents of the material, i. e. atoms, molecules, or the crystal lattice. For the specific property under consideration, these materials can be described in terms of continuous, homogeneous media on scales less than that of the nanostructure. The term mesoscopic is often reserved for electronic transport phenomena in systems structured on scales below the phase-coherence length A0 of the carriers. 

The integration of molecular-recognition-directed self-assembly and chemistry of bilayer membranes has lead to the development of mesoscopic supramolecular assemblies. The impartment of amphiphilicity to supermolecules drives their hierarchical self-assembly. The solvophilic-solvophobic interactions play a pivotal role in the determination of the supramolecular architecture, and this is a distinct feature from the earlier supramolecular chemistry. The combinatorial supramolecular approach is also effective to develop functional mesoscopic assemblies. In addition, combination of supramolecular polymers and solvent engineering will give a new perspective in the design of mesoscopic materials. 

The particulate materials in solids cause mixing to be complex The particles in such materials are small but finite in size moreover, they are isolated from each other, i.e., they are discrete. These characteristics render particulate materials mesoscopic. In general, the behavior of mesoscopic materials is describable neither by the firmly established laws of continuum mechanics valid for macroscopic materials, e.g., steel beams or large ice cubes, nor by the well-known principles of statistical mechanics applicable to microscopic materials, e.g., air. Any attempt to rigorously portray the motion of a countless number of interacting particles in a mixture by particle dynamics would be futile, as evidenced by the difficulty of portraying the motion of interacting particles as few as three. 

To conclude, when it comes to hydrothermal treatment, a lot of structural modification can occur depending on the experimental conditions. The key parameter in these structural changes is the flexibility of the silicate network. Apart from hydrothermal treatment, numerous other postsynthesis treatments have been described in order to reduce the pore size [21] or improve structural order, hydrothermal stability, and other characteristics of the mesoscopic materials [lOd]. 

Yoshikawa, Hiroyuki and Masuhara, Hiroshi Near-field Fluorescence Spectroscopy and Photochemistry of Organic Mesoscopic Materials in J. of Photochemistry and Photobiology C Photochemistry Reviews 1, 57-78 (2000). 

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