Metal vapor chemistry

Among the various preparative routes [1] metal vaporization chemistry provides a valuable S5mthetic route to weakly stabilized nanostructured metal particles [4]. 

Metal vapor chemistry showed that the lanthanides had quite an extensive chemistry with unsaturated hydrocarbons. Some of the early surveys of metal vapor reactions with unsaturated hydrocarbons included some lanthanide metals and showed that reactivity was present for these metals (14-18). Subsequent synthetic studies in which the products were isolated and characterized led to some of the most unusual organolanthanide complexes currently known (19-28). 

Although the structures of these species were not determined, this metal vapor chemistry clearly showed that unsaturated hydrocarbons were viable reagents for lanthanides. Furthermore, this high energy technique showed that new regimes of organolanthanide complexes were accessible under the appropriate conditions. In addition, attempts to understand the synthesis of the products in reac-... 

One of the earliest studies of zero valent lanthanide metal vapor chemistry involved the matrix isolation reaction of the metals with CO (73, 74). Based on infrared data, a variety of zero valent metal carbonyl complexes, Ln(CO) , n = 1-6, were postulated. These were not preparative scale experiments, however, and the reaction products were not stable except at very low temperature. Hence, unambiguous confirmation of the formula and structure of these complexes could not be obtained. 

From this brief exposure to the pervasive character of metal-vapor cryochemistry and matrix-isolation spectroscopy, it is clear that a field of multidisciplinary concern is surveyed. However, in this review, we shall focus on those accomplishments of greatest interest to the inorganic community in general, while pointing out, where applicable, the relevance of the results to other branches of chemistry and physics. 

Metal Vapor-Derived Nanostructured Catalysts in Fine Chemistry The Role Played by Particle Size in the Catalytic Activity and Selectivity... 

These metal vapor-derived nanostructured systems are valuable catalytic precursors for a wide range of reactions of great interest in fine chemistry. 

The field of gas-phase transition metal cluster chemistry has expanded rapidly due to the development of the laser vaporization source and the fast flow chemical reactor. The work from the three major laboratories have been reviewed. Many additional laboratories are developing cluster chemistry programs and will soon certainly make significant contributions. 

Blackborrow, J.R., and Young, D. In Metal Vapor Synthesis in Organometallic Chemistry Springer Verlag Berlin, 1979. 

Highly Reactive Organosamarium Chemistry via Metal Vapor and Sm(II) Syntheses... 

The metal vapor method also has played an important role in the development of organometallic lanthanide chemistry (6-10). This high energy technique demonstrated that the lanthanide metals had a much greater range of organometallic chemistry than had been assumed previously. The metal vapor technique applied to lanthanides identified reasonable new research goals which could subsequently be pursued by solution techniques. Not only the metal vapor reactions. 

Analysis of possible structures and reaction pathways in reactions 1-4 led to various model structures for these complexes (9t25). Some of these involved C-H activation of the substituents attached to the unsaturated carbon atoms. To test the validity of these models, two additional types of metal vapor reactions were examined. In one case, reactions with simpler unsubstituted hydrocarbons were examined. In another case, substrates ideally set up for oxidative addition of C-H to the metal center were examined. As described in the following paragraphs, both of these approaches expanded the horizons of organolanthanide chemistry. 

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