Europium(II) chloride
{{Chembox
| Name =
| ImageFile = Cotunnite_structure.png
| ImageSize =
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| ImageFile2 = Anode precipitate of EuCl2.jpg
| IUPACName =
| OtherNames = Europium dichloride
| Section1 = {{Chembox Identifiers
| CASNo = 13769-20-5
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo_Comment = dry
| CASNo2 = 70442-98-7
| CASNo2_Ref = {{cascite|correct|CAS}}
| CASNo2_Comment = dihydrate
| PubChem = 83719
| SMILES = Cl[Eu]Cl
| ChemSpiderID = 75541
| EC_number = 237-386-7
| StdInChI=1S/2ClH.Eu/h2*1H;/q;;+2/p-2
| StdInChIKey = BMANZYKPCBPZFG-UHFFFAOYSA-L
}}
| Section2 = {{Chembox Properties
| Eu=1 | Cl=2
| Appearance = white solid
| MeltingPt = {{convert|738|C|K}}Polyachenok, O. G.; Novikov, G. I. Saturated vapor pressures of SmCl2, EuCl2, YbCl2. Zhurnal Neorganicheskoi Khimii, 1963. 8 (12): 2631–2634. {{ISSN|0044-457X}}.
| BoilingPt = {{convert|2190|C|K}}
| Solubility = }}
| Section3 = {{Chembox Hazards
| MainHazards =
| FlashPt =
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| Section8 = {{Chembox Related
| OtherAnions = europium difluoride
europium dibromide
europium diiodide
| OtherCations = samarium dichloride
thulium dichloride
| OtherCompounds = europium trichloride}}
}}
Europium(II) chloride is an inorganic compound with a chemical formula EuCl2. When it is irradiated by ultraviolet light, it has bright blue fluorescence.{{cite journal |last1=Howell |first1=J.K. |last2=Pytlewski |first2=L.L. |title=Synthesis of divalent europium and ytterbium halides in liquid ammonia |journal=Journal of the Less Common Metals |date=August 1969 |volume=18 |issue=4 |pages=437–439 |doi=10.1016/0022-5088(69)90017-4}}
Preparation
Europium dichloride can be produced by reducing europium trichloride with hydrogen gas at high temperature:Klemm, Wilhelm; Doll, Walter. Measurements on the bivalent and the quadrivalent compounds of the rare earths. VI. The halides of bivalent europium. Zeitschrift für Anorganische und Allgemeine Chemie, 1939. 241: 233–238. {{ISSN|0044-2313}}.
: 2 EuCl3 + H2 → 2 EuCl2 + 2 HCl
If dry europium trichloride reacts with lithium borohydride in THF, it can also produce europium dichloride:Rossmanith, K.; Muckenhuber, E. Reaction of rare earth chlorides with lithium borohydride. II. Monatshefte fuer Chemie, 1961. 92: 600–604. {{ISSN|0026-9247}}.
: 2 EuCl3 + 2 LiBH4 → 2 EuCl2 + 2 LiCl + H2↑ + B2H6↑
Properties
Europium dichloride can form yellow ammonia complexes:EuCl2•8NH3, and can dissolve to pale yellowish EuCl2•NH3. Europium dichloride can react with europium hydride at 120-bar H2, producing EuClH that fluoresces green.{{cite journal|last1=Kunkel|first1=Nathalie|last2=Rudolph|first2=Daniel|last3=Meijerink|first3=Andries|last4=Rommel|first4=Stefan|last5=Weihrich|first5=Richard|last6=Kohlmann|first6=Holger|last7=Schleid|first7=Thomas|title=Green Luminescence of Divalent Europium in the Hydride Chloride EuHCl|journal=Zeitschrift für anorganische und allgemeine Chemie|volume=641|issue=7|year=2015|pages=1220–1224|issn=0044-2313|doi=10.1002/zaac.201400531|url=https://dspace.library.uu.nl/bitstream/handle/1874/321420/Kunkel_et_al_2015_Zeitschrift_f_r_anorganische_und_allgemeine_Chemie.pdf?sequence=1&isAllowed=y}}
References
{{reflist}}
{{europium compounds}}
{{chlorides}}
{{Lanthanide halides}}