Cluster magnesium

C. Reactions of Magnesium Clusters with Organic Substrates. 171... 

The sole gas-phase study on a cationic magnesium cluster examined the photodissociation spectrum of the Mg2(CH4)+" complex . Mg2 is only a minor product (equation 66) while Mg is the main ionic fragment and may arise via either of the processes shown in equations 67 and 68. The latter reaction is predicted to only be slightly more endothermic. 

Fig. 14.2. The structures of bare magnesium clusters ( - the most stable isomers).

The same composition of the magnesium cluster adducts with halides and hydrocarbons confirm the above conclusion that the composition of primary condensation products is determined by the competition between... 

Fig. 14.3. Calculated concentrations of various magnesium clusters in a codeposite film.

The reasons behind the existence of this correlation are considered in the next section. Before proceeding to the analysis of these reasons, let us formulate the major conclusion of Section 4 the magic number of nuclearity is a result of the optimal proportion between the energy and entropy factors in tetranuclear magnesium clusters. 

Magnesium clusters formed in the films and inserted into C-H and C-X bonds are tetranuclear. 

The tetranuclear magnesium cluster is rather stable, which makes it possible to obtain by transmetallation cluster alkyl Grignard reagents inaccessible by direct synthesis in the films of reagents. 

What are the processes in magnesium-organic halide films that lead to stabilization of tetranuclear magnesium clusters ... 

Noteworthy is, however, that we have recently employed basis sets of IGLO type, constructed by decontracting a DZP basis and adding an additional very tight inner s function and a diffuse d function, in studies of alkali metal complexes and cationic magnesium clusters [132, 133]. For these systems, atomic... 

P. (2005) Hydrogen storage in magnesium clusters quantum chemical study. Journal of the American Chemical Society, 127, 16675-16680. 

A chain mechanism for Grignard reactions involving slurries of small magnesium clusters has not been ruled out. but there arc plausible alternative interpretations of (lie evidence lSection 7.2.18). 

The insertion of magnesium clusters into C I" bonds raises the question whether magnesium... 

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