Lanthanide chalcogenates

Table 4 Selected lanthanide chalcogenates investigated by X-ray diffraction... 

Preliminary experimental results indicate that other lanthanide chalcogen-ides (Ln2S3, Ln2Se3) may also be accessible by a similar procedure in which the complexes 20 are treated in inert solvents with H2S or H2Se, respectively [38]. 

The first structurally characterized lanthanide chalcogen clusters were isolated as decomposition products of monomeric or dimeric species. Trivalent tellurolate complexes Ln[TeSi(TMS)3]3 (Ln = Ce, La), which can only be isolated as dmpe derivatives, decompose in solution to yield... 

The first compounds with lanthanide chalcogen bonds were prepared with ancillary Cp or Cp Ugands (see Trivalent Chemistry Cyclopentadienyl), because at the time it was believed that Cp steric demands were necessary to control chemical reactivity, and because the solubility of products in hydrocarbon solvents limited potential side reactions. Metathesis reactions governed by the insolubility of alkali halides were initially investigated (Reaction 1), but eventually a host of synthetic approaches were successfully employed. Compounds have been prepared by reduction of RE-ER with divalent Ln (Reaction 2), where the driving force of the reaction is increased stability associated... 

Kornienko AY, Emge TJ, Brennan JG (2001) Chalcogen-rich lanthanide clusters Cluster reactivity and the influence of andllary ligands on structure. J Am Chem Soc 123 11933-... 

Figure 4.2. The Periodic Table special collective names. The informal symbols of these families of elements are A = alkali metals, Ae = alcaline earth metals, Ln = lanthanides R = rare earth metals = Sc + Y + lanthanides, An = actinides, Hal = halogens, Chal = chalcogens,...

Figure 1.1 Principal features of the periodic table. The International Union of Pure and Applied Chemistry (IUPAC) now recommends Arabic group numbers 1-18 in place of the traditional Roman I—VIII (A and B). Group names include alkali metals (1), alkaline earth metals (2), coinage metals (11), chalcogens (16), and halogens (17). The main groups are often called the s,p block, the transition metals the d, block elements, and the lanthanides and actinides the / block elements, reflecting the electronic shell being filled. (See inside front cover for detailed structure of the periodic table.)...

Isobutyl complexes, with Zr(IV) and Hf(IV), 4, 903—904 Isocyanates, lanthanide-catalyzed polymerization, 4, 152 Isocyanides bis-silylation, 10, 747 chalcogen-chalcogen additions, 10, 752 with chromium... 

Much of this work has been directed towards materials-based applications, as volatile compounds might be CVD precursors see Chemical Vapor Deposition) and the ability of the thiolates and their fellows to react with the free chalcogens may assist doping lanthanide ions into optical and electrical materials. Thus, thermolysis of the [Ln(SePh)3(thf)3] (Ln =... 

The chemistry of the lanthanide elements boimd to the more electronegative chalcogen elements (E E = S, Se, Te) has been investigated extensively, particularly in the past decade, because this unconventional combination of highly ionic metals and highly covalent ligands leads to materials... 

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