Dysprosia

Dysprosium is a dense (specific gravity = 8.540) metal. It is soft, and when cut with a knife, it appears as a silvery metal that oxidixes slowly at room temperatures. The white oxide (Dy Oj) that forms on the outside of the metal sloughs off, exposing a fresh surface of the metal for more oxidation. The oxide of dysprosium is also called dysprosia. 

In the 1800s chemists searched for new elements by fractionating the oxides of rare-earths. Carl Gustaf Mosander s experiments indicated that pure ceria ores were actually contaminated with oxides of lanthanum, a new element. Mosander also fractionated the oxides of yttria into two new elements, erbium and terbium. In 1878 J. Louis Soret (1827—1890) and Marc Delafontaine (1837-1911), through spectroscopic analysis, found evidence of the element holmium, but it was contaminated by the rare-earth dysprosia. Since they could not isolate it and were unable to separate holmium as a pure rare-earth, they did not receive credit for its discovery. 

Boisbaudran discovers dysprosia and gadolinia, but finds that the latter is identical with an oxide discovered by Marignac in 1880. 

Divalent ions, ground state 111 Dy2Os 57, 58, 59 DyOCl 68 Dysprosia 2... 

Terbia — Erbia Holmia Cleve, 1879 Thulia Cleve, 1879 Holmia de Boisbaudran, 1886 Dysprosia de Boisbaudran, 1886 Neo-ytterbia Urbain—W elsbach, 1906-07... 

Chloride, DyClj, obtained by passing S,Cl2 over heated dysprosia. A hexahydrate is formed from the aq soln. The anhydr chloride, yellow shining crystals, d 3.67 mp 680°. LDj, in mice 585 mg/kg i.p. 7.65 g/kg orally, Haley et at. Toxical. App Pharmacol 8, 37 (1966). 

Interesting instances have been observed with rare earths. When the existence of the parallelism of the bond energies (and activation energies) with the magnetic moment was detected it turned out to be possible to expect definite results for those oxides of rare earths which at that time were not yet investigated. These expectations have been justified. In Fig. 1 in Tolstopyrntova and Balandin 435) the point for dysprosia (one of the two oxides whose purity was less than 99%) has... 

Mosander also separated yttria, another earth thought to be a pure oxide, into three yttria, erbia, and terbia, all named for the Swedish town of Ytterby. Other workers found other earths including lutetia (named for the ancient name for Paris), holmia (for the Latin name for Stockholm), thulia (from Thule, was the earliest name for Scandinavia), and dysprosia (from the Greek dysprositos, which means hard to get... 

Dysprosium oxide (dysprosia) Dy203 [1308-87-8] 373.00 Cubic D5s, cl80, Ia3, Mu203 type (Z=16) 8300 2408 7.74... 

K. Das and G. Banerjee, Mechanical Properties and Microstmctures of Reaction-Sintered Mullite-ZrOa Composites in the Presence of an Additive- Dysprosia,7. Ear. Ceram. Soc., 20,153-157 (2000). J.S. Moya and M.l. Osendi, Effect of ZrOa (ss) in Mullite on the Sintering and Mechanical Properties of Mullite/ZrOa Composites, 7. Mat. Sci. Lett., 2, 599-601 (1983). 

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