:Cobalt(II) cyanide
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| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 430345231
| Name = Cobalt(II) cyanide
| ImageFile =
| ImageName =
| IUPACName = Cobalt(II) cyanide
| OtherNames = cobaltous cyanide
|Section1={{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 61631
| InChI = 1/2CN.Co/c2*1-2;/q2*-1;+2
| SMILES = [Co+2].[C-]#N.[C-]#N
| InChIKey = CWZOMTYLSNXUEL-UHFFFAOYAR
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/2CN.Co/c2*1-2;/q2*-1;+2
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = CWZOMTYLSNXUEL-UHFFFAOYSA-N
| CASNo = 542-84-7
| CASNo_Ref = {{cascite|correct|??}}
| CASNo2_Ref = {{cascite|changed|??}}
| CASNo2 = 20427-11-6
| CASNo2_Comment = (dihydrate)
| CASNo3_Ref = {{cascite|changed|??}}
| CASNo3 = 26292-31-9
| CASNo3_Comment = (trihydrate)
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 3300OC3VVZ
| PubChem = 68336
| RTECS =
}}
|Section2={{Chembox Properties
| Formula = Co(CN)2
| MolarMass = 110.968 g/mol (anhydrous)
147.00 g/mol (dihydrate)
165.02 g/mol (trihydrate)
| Appearance = deep-blue powder
hygroscopic (anhydrous)
reddish-brown powder (dihydrate)
| Density = 1.872 g/cm3 (anhydrous)
| Solubility = insoluble{{RubberBible87th}}
| SolubleOther = dihydrate
degraded with dissolution by NaCN, KCN, NH4OH, HCl
| MeltingPtC = 280
| MeltingPt_notes = (anhydrous)
| BoilingPt =
| MagSus = +3825·10−6 cm3/mol
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|Section3={{Chembox Structure
| Coordination =
| CrystalStruct =
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|Section7={{Chembox Hazards
| ExternalSDS =
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|Section8={{Chembox Related
| OtherAnions = Cadmium chloride,
Cadmium iodide
| OtherCations = Zinc cyanide,
Calcium cyanide,
Magnesium cyanide
}}
}}
Cobalt(II) cyanide is the inorganic compound with the formula Co(CN)2. It is coordination polymer that has attracted intermittent attention over many years in the area of inorganic synthesis and homogeneous catalysis.
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Uses
Cobalt(II) cyanide has been used as a precursor to dicobalt octacarbonyl.{{cite book |first1= Heinz W. |last1= Sternberg |first2= Irving |last2= Wender |first3= Milton |last3= Orchin |first4= M. A. |last4= Lynch Jr. |first5= W. J. |last5= Sesny |title= Inorganic Syntheses |chapter= Cobalt Tetracarbonyl Hydride |series= Inorganic Syntheses |year= 1957 |volume= 5 |pages= 192–195 |doi= 10.1002/9780470132364.ch55|isbn= 9780470132364 }}
Preparation and structure
The trihydrate salt is obtained as a reddish-brown precipitate by adding two equivalents of potassium cyanide to a cobalt salt solution:{{cite book |doi=10.1002/9780470132333.ch72|chapter=Potassium Hexacyanocobaltate(III)|series=Inorganic Syntheses|year=1946|volume=2|last1=Bigelow|first1=John H.|first2=John C.|last2=Bailar Jr.|title=Inorganic Syntheses|pages=225–227|isbn=9780470132333}}
:CoCl2(H2O)6 + 2 KCN → Co(CN)2 + 2 KCl + 6 H2O
With excess cyanide, the red brown dicyanide dissolves to give pentacyanocobaltate.{{cite journal |doi=10.1080/01614946808064700|title=Reactions Catalyzed by Pentacyanocobaltate(II) |year=1968 |last1=Kwiatek |first1=Jack |journal=Catalysis Reviews |volume=1 |pages=37–72 }}
Solid cobalt(II) cyanide is a coordination polymer consisting of cobalt ions linked by cyanide units in a cubic arrangement, each such cobalt atom having octahedral geometry, and an additional cobalt atom in half of the cubic cavities.{{cite journal |journal= Angewandte Chemie International Edition |year= 1963 |volume=2 |issue= 7 |title= Cobalt(II) Cyanide, its Three-Demensional Frame-work Structure and Zeolitic Compounds |first1= Armin |last1= Weiss |first2= W. |last2= Rothenstein |page= 396 |doi= 10.1002/anie.196303962 }} That is, the structure is actually Co[Co(CN)3]2 in a zeolite-like structure. It forms hydrates and other inclusion complexes by having substances diffuse into the cavities that do not contain the cobalt atoms.
References
{{Cobalt compounds}}
{{Cyanides}}
{{inorganic-compound-stub}}