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A lanthanum hexaboride hot cathode. Lanthanum hexaboride cathodes. Lanthanum hexaboride powdered. Lanthanum hexaboride (La B 6, also called lanthanum boride and LaB) is an inorganic chemical, a boride of lanthanum. It is a refractory ceramic material that has a melting point of 2210 °C, and is insoluble in water and hydrochloric acid. [1]
The sum of the first two ionization energies for europium, 1632 kJ·mol −1 can be compared with that of barium 1468.1 kJ·mol −1 and europium's third ionization energy is the highest of the lanthanides. The sum of the first two ionization energies for ytterbium are the second lowest in the series and its third ionization energy is the ...
Lanthanide metals react exothermically with hydrogen to form LnH 2, dihydrides. [1] With the exception of Eu and Yb, which resemble the Ba and Ca hydrides (non-conducting, transparent salt-like compounds),they form black pyrophoric, conducting compounds [6] where the metal sub-lattice is face centred cubic and the H atoms occupy tetrahedral sites. [1]
Chemical formula Synonyms CAS number LaAlO 3: lanthanum aluminate: 71496–78–1 LaB 6: lanthanum boride: 12008–21–8 LaBr 3: lanthanum bromide: 13536–79–3 La(CHO 2) 3: lanthanum formate: 2081–11–0 LaC 2: lanthanum carbide: 12071–15–7 LaCl 3: lanthanum chloride: 10099–58–8 LaCl 3 •3H 2 O: lanthanum chloride trihydrate ...
formula Molecular weight (g/mol) Reference Yttrium acetate: C 6 H 9 O 6 Y: 266.038 [1] [2] Yttrium acetylacetonate: Y(C 5 H 7 O 2) 3: 388.233 [3] Yttrium(III) antimonide: YSb: 210.666 [4] Yttrium arsenate: YAsO 4: 227.828 [5] Yttrium arsenide: YAs: 163.828 [6] Yttrium boride: YB 25: 359.181 [7] Yttrium boride: YB 66: 802.432 [8] Yttrium bromide ...
The borides can be classified loosely as boron rich or metal rich, for example the compound YB 66 at one extreme through to Nd 2 Fe 14 B at the other. The generally accepted definition is that if the ratio of boron atoms to metal atoms is 4:1 or more, the compound is boron rich; if it is less, then it is metal rich.
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Lanthanum(III) bromide (LaBr 3) is an inorganic halide salt of lanthanum. When pure, it is a colorless white powder. The single crystals of LaBr 3 are hexagonal crystals with melting point of 783 °C. It is highly hygroscopic and water-soluble. There are several hydrates, La 3 Br·x H 2 O, of the salt also known. It is often used as a source of ...