Complex formation cluster

Most other studies have indicated considerably more complex behavior. The rate data for reaction of 3-methyl-l-phenylbutanone with 5-butyllithium or n-butyllithium in cyclohexane can be fit to a mechanism involving product formation both through a complex of the ketone with alkyllithium aggregate and by reaction with dissociated alkyllithium. Evidence for the initial formation of a complex can be observed in the form of a shift in the carbonyl absorption band in the IR spectrum. Complex formation presumably involves a Lewis acid-Lewis base interaction between the carbonyl oxygen and lithium ions in the alkyllithium cluster. 

Of course, it has to be assumed that the way of the clusters through the cell membrane and inside the cell is accompanied by numerous interactions with different and complex biomolecules however, the thermodynamically and kinetically most stable situation is reached with the DNA/cluster complex formation. 

In order to elucidate the causes of the increased stability of the hydrolyzed cluster ions compared with the unhydrolyzed ions, further studies were made of the behaviour of [Te2X8]3 (where X = Cl,Br, or I) in solutions of hydrogen halides [43,52,80,87]. The studies were performed mainly in relation to the most stable and most readily synthesized [Tc2C18]3- ion (Fig. la) kinetic methods with optical recording were employed. The identity of the reaction products was in most cases confirmed by their isolation in the solid phase. The studies showed that the stability of the [Tc2X8]3 ions (where X = Cl, Br, or I) in aqueous solutions is determined by the sum of competing processes acid hydrolysis complex formation with subsequent disproportionation and dissociation of the M-M bonds, and oxidative addition of atmospheric oxygen to the Tc-Tc multiple bond. 

However, a detailed model for the defect structure is probably considerably more complex than that predicted by the ideal, dilute solution model. For higher-defect concentration (e.g., more than 1%) the defect structure would involve association of defects with formation of defect complexes and clusters and formation of shear structures or microdomains with ordered defect. The thermodynamics, defect structure, and charge transfer in doped LaCo03 have been reviewed recently [84],... 

The "classical" theory of nucleation concentrates primarily on calculating the nucleation free energy barrier, AG. Chemical interactions are included under the form of thermodynamic quantities, such as the surface tension. A link with chemistry is made by relating the surface tension to the solubility which provides a kinetic explanation of the Ostwald Step Rule and the often observed disequilibrium conditions in natural systems. Can the chemical model be complemented and expanded by considering specific chemical interactions (surface complex formation) of the components of the cluster with the surface ... 

Sulfide minerals were formed mostly hydrothermally from post-magnetic fluids it appears remarkable that the formation of many ore deposits cannot be conclusively explained because of the very low solubility of the corresponding sulfide. Though it was postulated earlier (28, 29, 95) that polysulfido complexes might have been responsible for the transport of metals and sulfur together (80), it was later proved that many discrete polysulfido complexes and clusters of metals exist in polysulfide solutions (see, e.g., 136,138). 

Digermanium hexachloride, synthesis in electric discharge, 6 173, 272 Diglycolic acid, complex formation by, 3 276 Digold heteronuclear cluster compounds. X-ray crystallography, 39 358-362... 

This aromatic solvent induced shift (ASIS) is explained by the formation of preferential collision complexes or clusters of aromatic solvent molecules in the vicinity of the polar groups of the solute, so that the effect of the solvent magnetic anisotropy within the space occupied... 

Atomic clustering or atomic complex formation in materials can also... 

The selective effect that a salt can have on the volatilities of the two liquid components, and hence on the composition of the equilibrium vapor, comes about primarily through effects exerted by the salt ions and/or molecules on the structure of the liquid phase. The most likely effect to be expected is that the salt would induce formation of association complexes, or clusters, of molecules of the volatile components about its ions. This effect would lower both of their volatilities but by differing amounts depending on the degree of selectivity of the particular salt in the preference of its ions for clustering with the molecules of one volatile component over those of the other. A preference for associating with the less volatile component would result in an increase in relative volatility and hence in ease of separation, and a preference for the more volatile component would have the opposite effect. 

The opposite effect on quenching by neutral molecules when small amounts of detergent are added to aqueous solutions of 3 could be attributed to several possible factors. First, the addition of detergent to the polymer may help in affording a more hydrophobic environment in its vicinity that may enhance the polymer-small molecule association. Also, since surfactants such as DTAB are well known to solubilize organic molecules in water, it appears reasonable that clusters of the detergent may combine with the neutral quenchers and function as chaperones to increase their effective solubility and thus enhance the complex formation with the polymer. 

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