Structural changes with aluminum

The aim of this manuscript is to examine the molecular structure of the IL as the ratio of Al/RMIM" was changed with and without HCl added. The working hypothesis is that the aluminum speciation determines the reactivity of the IL and this speciation depends upon the structure of RMIM. ... 

On warming, gray (or a) tin, with a cubic structure changes at 13.2°C into white (or j0) tin, the ordinary form of the metal, which has a tetragonal structure. When tin is cooled below 13.2°C, it changes slowly from white to gray. This change is affected by impurities such as aluminum and zinc and can be prevented by small additions of antimony or... 

Changing the aluminum content has a significant effect on the relative stability of zeolite structures with very different topology. While the heat of formation of the wide-pore zeolite is affected very little, the heats of formation of the medium-pore zeolites fall significantly. 

The structure of aluminate in aqueous solution is gradually decomposed and the moiety of the network structure of aluminate, aluminum tetrahydroxide, and the hydrates occur as the predominant chemical species in the aqueous solution. The structure of chemical species in aqueous solution changes from fourfold coordination structure to sixfold coordination structure with H20 molecules. At this time, polymerization begins to proceed. Hexaaquaaluminum cation serves as a core to form the network structure of Al(OH)3 by the progress of polymerization. Finally, Al(OH)3 precipitates and crystallizes. 

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