Vanadium(II) iodide
{{Chembox
| ImageFile = Cadmium-iodide-3D-layers.png
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|Section1={{Chembox Identifiers
| CASNo = 15513-84-5
| CASNo_Ref = {{cascite|correct|CAS}}
| PubChem = 84959
| ChemSpiderID = 76640
| EC_number = 239-545-6
| StdInChI=1S/2HI.V/h2*1H;/q;;+2/p-2
| StdInChIKey = OJFNQCZRUJTCOZ-UHFFFAOYSA-L
| SMILES = [V+2].[I-].[I-]
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|Section2={{Chembox Properties
| Formula = VI2
| MolarMass =
| Appearance = black mica-like
| Density = 5.44 g/cm3
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|Section3={{Chembox Hazards
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|Section8={{Chembox Related
| OtherAnions = vanadium(II) chloride, vanadium(II) bromide
| OtherCompounds = vanadium(III) iodide
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Vanadium(II) iodide is the inorganic compound with the formula VI2. It is a black micaceous solid. It adopts the cadmium iodide structure, featuring octahedral V(II) centers.{{cite journal |doi=10.1002/zaac.19422490204|title=Zur Kenntnis der Dihalogenide des Titans und Vanadins|year=1942|last1=Klemm|first1=Wilhelm|last2=Grimm|first2=Ludwig|journal=Zeitschrift für Anorganische und Allgemeine Chemie|volume=249|issue=2|pages=198–208}} The hexahydrate [V({{H2O-nl}})6]I2, an aquo complex, is also known. It forms red-violet crystals. The hexahydrate dehydrates under vacuum to give a red-brown tetrahydrate with the formula V({{H2O-nl}})4I2.{{cite journal |doi=10.1002/zaac.19623150108|title=Darstellung von Vanadin(II)-Verbindungen aus wäßriger Lösung|year=1962|last1=Seifert|first1=Hans-Joachim|last2=Gerstenberg|first2=Burkhard|journal=Zeitschrift für Anorganische und Allgemeine Chemie|volume=315|issue=1–2|pages=56–63}}
Preparation
The original synthesis of VI2 involved reaction of the elements.
Solvated vanadium(II) iodides can be prepared by reduction of vanadium(III) chlorides with trimethylsilyl iodide.{{cite journal |doi=10.1039/DT9940003683|title=Preparation of New Vanadium(II) Iodides and Crystal Structure of Hexakis(acetonitrile)vanadium(II)(Tetraiodide)|year=1994|last1=Hitchcock|first1=Peter B.|last2=Hughes|first2=David L.|last3=Leigh|first3=G. Jeffery|last4=Sanders|first4=J. Roger|last5=De Souza|first5=Jaisa|last6=McGarry|first6=Celine J.|last7=Larkworthy|first7=Leslie F.|journal=Journal of the Chemical Society, Dalton Transactions|issue=24|pages=3683}} It reacts with anhydrous ammonia to give the hexaammine complex.{{cite journal |doi=10.1002/zaac.19966220709|title=Isotype Strukturen einiger Hexaamminmetall(II)-halogenide von 3d-Metallen: V(NH3)6I2, Cr(NH3)6I2, Mn(NH3)6Cl2, Fe(NH3)6Cl2, Fe(NH3)6Br2, Co(NH3)6Br2 und Ni(NH3)6Cl2|year=1996|last1=Eßmann|first1=Ralf|last2=Kreiner|first2=Guido|last3=Niemann|first3=Anke|last4=Rechenbach|first4=Dirk|last5=Schmieding|first5=Axel|last6=Sichla|first6=Thomas|last7=Zachwieja|first7=Uwe|last8=Jacobs|first8=Herbert|journal=Zeitschrift für Anorganische und Allgemeine Chemie|volume=622|issue=7|pages=1161–1166}}