Halides scandium

Gurvich LV, Ezhov YuS, Osina EL, Shenyavskaya EA (1999) The structure of molecules and the thermodynamic properties of scandium halides. Russ J Phys Chem 73 331—344... 

Giricheva NI, Lapshin SB, Girichev GV (1996) Sttucmral, vibrational, and energy characteristics of halide molecules of group II-V elements. J Struct Chem 37 733-746 Gurvich LV, Ezhov YuS, Osina EL, Shenyavskaya EA (1999) The structure of molecules and the thermodynamic properties of scandium halides. Russ J Phys Chem 73 331-344 Birge RT (1925) The law of force and the size of diatomic molecules, as determined by their band spectra. Nature 116 783-784... 

Other reduced scandium halides such as SC7CI12 and ScCl are not free of interstitial atoms (H, C, N) although ScCl , which crystallizes just like ZrCl, has a double layer structure which would be the end member of further condensation of edge-connected octahedral chains. 

Table 30.5 Stoichiometries and structures of reduced halides (X/M < 2) of scandium, yttrium, lanthanum and the lanthanides...

The first compound of this series, CeSI, was reported by Carter (68) in 1961, and later discussed by Dagron (93). It was obtained by the reaction of iodine with cerium sulfide at 430 C, or by direct synthesis from the elements at 500°C. This was the start of a detailed investigation of this group of compounds mainly by Dagron and co-workers. The present situation is presented in Table VII. No scandium compounds are known thus far, and the same is true for selenium and tellurium halides of these elements. 

Calcium metal is an excellent reducing agent for production of the less common metals because of the large free energy of formation of its oxides and halides. The following metals have been prepared by the reduction of their oxides or fluorides with calcium hafnium (22), plutonium (23), scandium (24), thorium (25), tungsten (26), uranium (27,28), vanadium (29), yttrium (30), zirconium (22,31), and most of the rare-earth metals (32). 

Many highly reduced halides of scandium, yttrium, and zirconium have been found to have infinite metal-metal bonded chains.169 Zirconium chloride, for example, contains double metal layers alternating with double chlorine layers (Fig. 16.68). It was dis-... 

The use of solid supported, recyclable catalysts, is a well-assessed technique in classic organic chemistry, and many exhaustive reviews dealing with this subject are available [105, 115]. The use of solid supported catalysts for library synthesis in solution has also been reported. Among others, Kobayashi et al. presented the use of a new supported scandium catalyst for 3CC reactions leading to solution libraries of amino ketones, esters, and nitriles (24-member model discrete library) [116], or to quinolines (15-member model discrete library) [117], and Jang [118] presented a polymer bound Pd-catalyzed Suzuki coupling of organoboron compounds with halides and triflates. This area was also briefly reviewed recently [119]. 

All four scandium(III) halides are known, all but the fluoride (WO3 structure) having the FeCfr structure. They can be obtained as white solids directly from the elements and in some cases by dehydration of the hydrated salts, as well as by thermal decomposition of (NH4)3ScX6 (X = Cl, Br), a method also used for the lanthamdes. Gas-phase studies have identified isolated planar SCF3 molecules at 1750K ScCfr molecules with a very slight pyramidal distortion and both monomers and dimers in Scfr vapour at 1050 K. 

Scandium By-product A1 alloys halide lighting additive... 

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