Yttrium fluoride

Anion Interstitials The other mechanism by which a cation of higher charge may substitute for one of lower charge creates interstitial anions. This mechanism appears to be favored by the fluorite structure in certain cases. For example, calcium fluoride can dissolve small amounts of yttrium fluoride. The total number of cations remains constant with Ca +, ions disordered over the calcium sites. To retain electroneutrality, fluoride interstitials are created to give the solid solution formula... 

Bowlby BE, Di Bartolo B (2003) Spectroscopy of Trivalent Praseodymium in Barium Yttrium Fluoride 106 193-208... 

Yttrium oxalate is then ignited to its oxide, Y2O3. The oxide is heated at 750°C in a stream of anhydrous hydrogen fluoride to yield yttrium fluoride, YF3. Alternatively, the oxide is mixed with ammonium hydrogen fluoride NH4HF2 and heated at 400°C in a stream of dry air or helium. Yttrium metal may be produced from its fluoride either by metallothermic reduction or electrolysis. The more common metallothermic reduction involves reducing the fluoride with redistilled calcium in 10% excess over the stoichiometric amounts at elevated temperatures ... 

In the electrolytic process, a fused bath of yttrium fluoride and lithium fluoride is heated to nearly 1,700°C and electrolyzed. The electrolysis is done in a graphite crucible using molybdenum cathodes at which yttrium is produced as molten metal. 

G. M. Herbert, H. Insley, and C. F. Weaver Phase equilibria in the system sodium fluoride-yttrium fluoride. Inorg. Chem. 2, 1005 (1963). 

The only other route to scandium fluoride derivatives has been via C—F bond activation of fluoro-alkenes with [ScR(Cp )2] (R = H, Me) to give [ScF(Cp )2] [1], Very recent work has produced the first report of an organometallic yttrium fluoride. The reaction between [(CsH5)3Y] and Me3NHF results in the isolation of [ (C5H5)2YF(THF) 2] which has been fully characterised by elemental analysis, infra-red, mass and NMR spectroscopies and X-ray diffraction [8]. 

Yttrium is usually bought and sold in the form of yttrium oxide (Y2O3). In 2007, yttrium oxide sold for about 50 per kilogram. The pure metal can be obtained by combining another compound of yttrium, yttrium fluoride (YF3), with calcium metal at high temperatures ... 

If a small amount of yttrium fluoride was heated over an extended period with calcium fluoride, would you expect a substitutional solid solution to form How could the difference in charge of yttrium and calcium be accommodated ... 

Nanoneedle YF3 The microwave and IL methods developed by our group have been found to be very efficient and simple, compared to other methods employed in the past for the fabrication of rare earth fluorides. To obtain yttrium fluoride nanoneedles we first had to prepare yttrium nitrate, which is obtained by refluxing yttrium oxide in a nitric acid. In the next step, the yttrium nitrate is dissolved in the IL, and then heated in a domestic microwave oven. We examined the product during the course of... 

Thermal Stabilization of Fluorite and Rhombic Yttrium Fluoride Systems. Abstracts of the Fifth Conference on Crystallography, Tiflis, SSSR, vol. 2 (Akad. Nauk SSSR) pp. 25-26. 

Kramer, K., Biner, D., Frei, G., Gtidel, H.U., Hehlen, M.P., Ltithi, R.S., 2004. Hexagonal sodium yttrium fluoride based green and blue emitting upconversionphosphors. Chem. Mater. 16, 1244-1251. 

His suspicion, of course, had antecedents. Heinrich Rose discovered earlier that yttrium chloride itself is not volatile, although it was thought to be so earlier. What appears volatile is the impurity beryllium chloride. This finding spoke in favour of yttrium not being a pure element as believed earlier. Rose was the first to prepare metallic yttrium by reducing yttrium chloride and yttrium fluoride with metallic sodium. It turned out later, however, that this yttrium metal was still largely contaminated. 

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