Molecular layering method

THE MOLECULAR LAYERING METHOD PROGRESS IN SCIENCE AND PRACTICAL WORKS FOR CREATION OF FUNCTIONAL NANOMATERIALS... 

Keywords nanotechnology, nanomaterials, molecular layering method, adsorbents, catalysts, nanoceramic, nanocomposition materials, pigments, nanofillers, polymers, retardants of combustibility... 

The Molecular Layering Method as a Base of Chemical Nanotechnology... 

Figure 1. The chemical design of nanostructures on the surface of solids by the molecular layering method.

Fundamental concepts of the molecular layering method have been developed and applied by the team headed by Professor Valentine Aleskovsky in Russia. This method, similar to atomic layer epitaxy and atomic layer deposition, has been used to create monolayers on oxides and polymers as humidity sensors, flame retardants, and agents to enhance sintering in ceramic materials. 

A. A. Malygin, The molecular layering method as a basis of chemical nanotechnology, in Natural Microporous Materials in Environmental Technology (Kluwer Academic Publishers, 1999), pp. 487-495. 

A. A Malygin, Synthesis of Multicomponent Oxide Low-Dimension Systems on Surface of Porous Silicon Dioxide Using Molecular Layering Method, J. General Chem. (in Russian) 72(4), 617-632 (2002). 

The chemical basis of surface modification technology of silica and alumina by molecular layering method... 

THE MODIFICATION OF STRUCTURAL AND ADSORPTION CHARACTERISTICS OF SILICA AND ALUMINA BY THE MOLECULAR LAYERING METHOD... 

Another method has also been suggested for tethering [23]. This would require all the molecules designated as the membrane molecules to be tethered to some or all of their neighbors, that are also part of the membrane. Fig. 1 shows the typical structure of a semi-permeable membrane while Fig. 2 shows a typical MD simulation system for osmosis with each membrane one molecular layer thick. In addition, as can be seen from Fig. 2, it is not necessary for the simulation system to be a cube. In fact it is desirable for... 

The simulations to investigate electro-osmosis were carried out using the molecular dynamics method of Murad and Powles [22] described earher. For nonionic polar fluids the solvent molecule was modeled as a rigid homo-nuclear diatomic with charges q and —q on the two active LJ sites. The solute molecules were modeled as spherical LJ particles [26], as were the molecules that constituted the single molecular layer membrane. The effect of uniform external fields with directions either perpendicular to the membrane or along the diagonal direction (i.e. Ex = Ey = E ) was monitored. The simulation system is shown in Fig. 2. The density profiles, mean squared displacement, and movement of the solvent molecules across the membrane were examined, with and without an external held, to establish whether electro-osmosis can take place in polar systems. The results clearly estab-hshed that electro-osmosis can indeed take place in such solutions. 

There is difficulty in defining the absolute mobilities of the constituent ions in a molten salt, since it does not contain fixed particles that could serve as a coordinate reference. Experimental means for measuring external transport numbers or external mobilities are scarce, although the zone electromigration method (layer method) and the improved Hittorf method may be used. In addition, external mobilities in molten salts cannot be easily calculated, even from molecular dynamics simulation. 

When this surface is reacted with methanol, then methoxy is formed as demonstrated by a variety of techniques, including molecular beam methods [12], TPD [12,13], IRAS [14] and UPS [15]. Fig. 4a shows a layer of oxygen which has partially reacted and formed... 

Despite the availability of fast computers and efficient codes for accurate quantum chemistry calculations, it is not likely in the near future that we will be able to study chemical reactions in proteins taking all the proteins atoms into quantum mechanical calculations. Hybrid methods in which different parts of large molecular systems are treated by different theoretical levels of methods are likely to play a key role in such studies for the coming decade or more. The ONIOM method we have developed is a versatile hybrid method that allows combining different quantum mechanical methods as well as molecular mechanics method in multiple layers, some features of... 

Molecular mixing method for improvement of the molecular orientation in monomolecular layer... 

Auger spectroscopy yields data for molecular layers from which relatively accurate and precise packing densities and elemental analyses are obtained. Two methods are available, allowing verification of precision and self-consistency. The first of these methods is based upon measurement of elemental Auger signals (Iq, In, Iq, etc.), while the other method measures the at-... 

The table shows that many molecules are far from being symmetrical in shape, a direct confirmation of his theory. We notice incidentally the need for care in calculating the number of molecular layers contained in a thin film by the method of Rayleigh and Devaux, without further consideration. (If for example Devaux had chosen cerotic acid instead of triolein as his test case, he would have found 31 A. as the thickness of the film, whereas the cube root of the volume of a molecule is 31x25 = 9 2 A. Thus, neglecting the shape of the molecule, cerotic acid would have appeared to form a trimolecular layer.)... 

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