Cluster complexes selenium

Examples of other interesting additions (225) across the Rh=Rh bond include complexes of S02 (96 ) (225,230,231), selenium (97 ) (225,232), tellurium (225), sulfur (225,233), and AuCl [from AuCl(CO)] (225,230). The latter reaction results in a Rh2Au triangle and is just one of a large number of heteropolymetallic cluster complexes built up from 4 and 5 (see below). 

Table 26.3 (continued) BDEs in Selenium Clusters/Complexes... 

Se-O bonds, 452 Se-P bonds, 452 Se-S bonds, 452 Se-Se bonds, 451 Se-Te bonds, 452 Selenium clusters/complexes anions, 1346 cations, 1341-1346 neutrals, 1341 Si-containing compounds C-H bonds, 100, 131, 133 C-O bonds, 344 N-C bonds, 418 N-H bonds, 377 O-H bonds, 261, 304 0-0 bonds, 315 Si-Br bonds, 465 Si-C bonds, 460-462 Si-Cl bonds, 464-465 Si-F bonds, 463 -464 Si-Ge bonds, 467 Si-H bonds, 455-459 Si-1 bonds, 465 Si-Mn bonds, 467 Si-N bonds, 463 Si-O bonds, 462-463 Si-P bonds, 466 Si-S bonds, 466 Si-Se bonds, 450,466 Si-Si bonds, 459-460 Si-Sn bonds, 467 Si-Te bonds, 466 Silicon neutral complexes anions, 1153 cations, 1147-1152 neutrals, 1140-1147 Sm-containing species neutrals, 623 -626 Sm clusters, 626 Sn-containing compounds 0-0 bonds, 315 Sn-Br bonds, 475-476 Sn-C bonds, 476-477 Sn-Cl bonds, 475 Sn-F bonds, 475 Sn-Ge bonds, 475 Sn-H bonds, 473-474 Sn-1 bonds, 476 Sn-O bonds, 477 Sn-Pb bonds, 475 Sn-S bonds, 477 Sn-Se bonds, 477 Sn-Si bonds, 467 Sn-Sn bonds, 474-475 Sn-Te bonds, 477 Sr-containing species neutrals, 591-593 Sr+ clusters, 593-595 Sulfates... 

Within this context, the present article concentrates on transition metal cluster complexes of cobalt, iron and manganese with mixed chalcogen/carbonyl ligand spheres obtained by reaction of simple binary metal carbonyls with alkali-metal sulfides, alkali-metal thiolates or transition-metal thiolate complexes and their selenium or tellurium counterparts. 

Metal thiolate complexes will reduce elemental sulfur or red selenium via the oxidative elimination of RSSR. In a similar manner, metal selenolate complexes ean be used to reduce elemental selenium. The resulting E ligands favor the formation of polynuclear cluster complexes, due to the greater tendency of E (vs. RE ) to form bridging interactions between metal centers. Originally developed in the synthesis of [Fe4Se4(SPh)4], this method has been well utilized in the synthesis of a number of iron thiolate/sulfide clusters, as well as their selenide counterparts (Equation (5)). More recently, sulfur- and selenium-containing lanthanide clusters (see Section 7.2.5.5) have been synthesized by the displacement of ER from Ln(ER)3 ... 

Perspectives for fabrication of improved oxygen electrodes at a low cost have been offered by non-noble, transition metal catalysts, although their intrinsic catalytic activity and stability are lower in comparison with those of Pt and Pt-alloys. The vast majority of these materials comprise (1) macrocyclic metal transition complexes of the N4-type having Fe or Co as the central metal ion, i.e., porphyrins, phthalocyanines, and tetraazaannulenes [6-8] (2) transition metal carbides, nitrides, and oxides (e.g., FeCjc, TaOjcNy, MnOx) and (3) transition metal chalcogenide cluster compounds based on Chevrel phases, and Ru-based cluster/amorphous systems that contain chalcogen elements, mostly selenium. 

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