Organic-inorganic molecular beam

ENGLAND ET AL. Organic—Inorganic Molecular Beam Epitaxy... 

The flowering of molecular beam chemistry has been delightfully illustrated by Herschbach [361], He distinguishes 15 families of reaction of the atom + diatomic molecule type (103 reactions in all) that have been studied. Table 1.6 is reproduced from his paper and lists these classes of reaction to complete this inventory it is necessary to add the reactions of (a) metal atoms with organic and inorganic polyatomic molecules, (b) methyl radicals... 

The alkaline earth metals form a host of unique monovalent free radicals. Most of these molecules can be formed by the laser-driven chemical reactions of metal vapors with a wide variety of organic and inorganic molecules. This photochemical production of new molecules has led to an extensive gas-phase inorganic chemistry and spectroscopy of alkaline earth derivatives. In recent years, the Broida oven source has been displaced by the pulsed molecular beam spectrometer. The chemical dynamics and photochemistry of these new molecules are still at a very early stage of investigation. 

Chapter 1 deals with the kinetics of the dissociation of diatomic molecules and the recombination of atoms, and Chapters 2 and 3 with the reactions of atoms and radicals with molecules, abstraction (metathetical) processes and addition to double and triple bonds. Data for the reactions of metal atoms with a variety of inorganic, organic and metal organic compounds, derived from sodium flame and molecular beam techniques, are discussed in Chapter 4 and rapid substitution at labile metal ions in solution in Chapter 5. The theory of, and the experimental results for, ion-molecule reactions, i.e. chemical processes resulting from binary collisions of positive or negative ions with neutral molecules, are discussed in Chapter 6 and the reactions of solvated electrons in Chapter 7. 

The most flexible methods, which can be applied in principle to nearly all molecules and which provide the most important techniques for the preparation of organic molecular films, are vacuum evaporation and molecular-beam epitaxy (cf [14]). In both methods, the substance required is evaporated or sublimed and captured on a substrate which is cooled as necessary. In molecular-beam epitaxy, the substrate must be an (inorganic) single crystal. The nature of the substrate s surface, its temperature and the velocity of evaporation or sublimation, adjustable... 

As a consequence one might expect that the future needs to rely on hybrid elements which arise from advanced UV-and electron-beam lithography, from imprint techniques or automated and parallelized nanomanipulation techniques, like dip-pen lithography or focused ion-beam techniques in combination with supramolecular approaches for the assembly of molecular inorganic/organic hybrid system. Nevertheless, it is evident for any kind of chemical approach that falling back onto the present-day... 

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