Yttrium susceptibility

Abstract The magnetic susceptibility of underdoped yttrium and lanthanum cup-... 

Fig. 28. Paramagnetic susceptibilities of (a) yttrium and (b) gadolinium ferrogarnets. Solid lines are theoretical curves based on molecular field model and empirically determined molecular field constants. Dashed lines are experimental curves indicating effects of short-range order in the neighborhood of the Curie temperature. (After A16onard (5).)...

Ionic systems - less susceptible to deleterious dimerization - are accessible with a Judicious choice of ancillary ligand. The /3-diketoiminate scandium dimethyl complex (7) (Figure 11 Ar = 2,6-diisopropylphenyl), activated by B(C6Fs)3 leads to a structurally characterizable ionic complex which polymerizes ethylene. The neutral 1,4,7-triazocyclononane ligand was used to prepare a scandium trimethyl complex (8), which polymerizes ethylene when B(CeF5)3 is used as a cocatalyst. A derivative pendant amide arm leads to the yttrium bis (trimethylsilylmethyl) compound (9), which exhibits modest activity in the presence of [HNMe2Ph][B(C6F5)4l.= ... 

Chemical Studies.—Mixed ligand complexes of scandium have been obtained containing edta and either Tiron, sodium 2,3-dihydroxynaphthalene-6-sulphonate, or pyrocatechol. These mixed complexes are generally more stable than their yttrium analogues, but are more susceptible to hydrolysis. The stability of tartrate complexes has also been investigated. ... 

Gas turbine blades are essentially nickel-base or cobalt-base alloys containing substantial amounts of chromium, several percent aluminum, and a few hundredths percent yttrium. Their susceptibility to hot corrosion and sulfidation has already been discussed. Applied coatings of aluminum or of aluminum-chromium-yttrium increase resistance to attack. 

Fig. 6.26, Susceptibility of yttrium, scandium, lanthanum and lutetium (after Spedding and Croat 1973a, b).

Another subject class is concerned with diluted 4f metals. Sarkissian and Coles (1976) have tried to distinguish between spin-glass freezing and helical ordering in solid solutions of Gd, Tb and Dy in Y and Sc by means of resistivity and susceptibility measurements (fig. 12). These materials have attracted recent interest again, because some are candidates for anisotropic spin glasses (Baberschke et al. 1984). It also turned out that spin-glass behavior in yttrium based alloys occurs at much lower concentrations than previously claimed. 

Geochemical studies often require determination of all the lanthanides (and often yttrium as well) in various geological matrices such as rocks, sediments, coal, etc. In most geological matrices, the light rare earths (e.g.. La and Ce) are much more abundant than the heavier rare earths (e.g., Tb and Tm). Therefore, the analytical technique for this application should have multi-element capabilities, large dynamic range, and limited susceptibility to interferences. This problem was not easily fulfilled before the advent of ICP-AES, which provided the first analytical technique with the potential to cover the whole suite of rare earths in a reasonable time. 

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