Manganese(II) iodide
{{chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 443265422
| Name = Manganese(II) iodide
| ImageFile1 = Manganese(II)-iodide-xtal-layer-3D-bs-17.png
| ImageName1 = Ball-and-stick model of part of a layer in the crystal structure of manganese(II) iodide
| ImageFile2 = Manganese(II)-iodide-xtal-packing-3D-bs-17.png
| ImageName2 = Ball-and-stick model of layer stacking in the crystal structure of manganese(II) iodide
| ImageFile3 = MnI2(aq)4.svg
| ImageName3 = Molecular structure of manganese(II) iodide tetrahydrate
| IUPACName = Manganese(II) iodide
| OtherNames =
|Section1={{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|??}}
| CASNo = 7790-33-2
| CASNo1 = 7790-33-2
| CASNo1_Comment = tetrahydrate
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 5Q9VVO3QCN
| RTECS =
| PubChem = 82250
| EINECS = 232-201-6
| SMILES = [Mn+2].[I-].[I-]
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 74227
| InChI = 1/2HI.Mn/h2*1H;/q;;+2/p-2
| InChIKey = QWYFOIJABGVEFP-NUQVWONBAL
| StdInChI_Ref = {{stdinchicite|changed|chemspider}}
| StdInChI = 1S/2HI.Mn/h2*1H;/q;;+2/p-2
| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}
| StdInChIKey = QWYFOIJABGVEFP-UHFFFAOYSA-L
}}
|Section2={{Chembox Properties
| Formula = MnI2
| MolarMass = 308.747 g/mol
| Appearance = pink crystalline
| Density = 5.01 g/cm3
| Solubility = soluble
| MeltingPtC = 701
| MeltingPt_notes = (anhydrous)
80 °C (tetrahydrate)
| BoilingPtC = 1033
| MagSus = +14,400·10−6 cm3/mol
}}
|Section3={{Chembox Structure
| Coordination = octahedral
| CrystalStruct = Rhombohedral, hP3, SpaceGroup = P-3m1, No. 164
| Dipole =
}}
|Section7={{Chembox Hazards
| NFPA-H = 1
| NFPA-F = 0
| NFPA-R = 1
| GHSPictograms = {{GHS08}}
| GHSSignalWord = Danger
| HPhrases = {{H-phrases|360}}
| PPhrases = {{P-phrases|201|202|281|308+313|405|501}}
{{cite web |url= http://www.sigmaaldrich.com/catalog/search/ProductDetail/ALDRICH/223646 |title= 223646 Manganese(II) iodide 98% |access-date=2011-08-05 |publisher= Sigma-Aldrich|date= }}
| FlashPt = non-flammable
}}
|Section8={{Chembox Related
| OtherAnions = Manganese(II) fluoride
Manganese(II) chloride
Manganese(II) bromide
| OtherCations = Iron(II) iodide
Cobalt(II) iodide
}}
}}
Manganese(II) iodide is the chemical compound composed of manganese and iodide with the formula MnI2(H2O)n. The tetrahydrate is a pink solid while the anhydrous derivative is beige. Both forms feature octahedral Mn centers. Unlike MnCl2(H2O)4 and MnBr2(H2O)4 which are cis, MnI2(H2O)4 is trans.
Preparation
Anhydrous MnI2 is prepared from the elements:{{cite journal |doi=10.1055/s-1984-30724 |title=Organomanganous Reagents; IX. Preparation of Various Halogenated, Alkoxylated, Aryloxylated, and Arylsulfenylated Ketones from Correspondingly Functionalized Carboxylic Acid Chlorides or Anhydrides |date=1984 |last1=Friour |first1=G. |last2=Cahiez |first2=G. |last3=Normant |first3=J. F. |journal=Synthesis |volume=1984 |pages=37–40 |s2cid=94812612 }}
:{{chem2| Mn + I2 -> MnI2}}
The tetrahydrate can be prepared by treating manganese(II) carbonate with hydriodic acid. The anhydrous form can be produced from it by dehydration in a vacuum.{{cite journal |doi=10.1016/S0020-1693(00)90464-X |title=The Coordination Chemistry of Manganese |date=1981 |last1=Hosseiny |first1=Afshin |last2=MacKie |first2=Anthony G. |last3=McAuliffe |first3=Charles A. |last4=Minten |first4=Karl |journal=Inorganica Chimica Acta |volume=49 |pages=99–105 }}
Properties
Samples turn brown in air under the influence of light as a result of the oxidation of the iodide ion to iodine.{{Cite book |last=Ans |first=Jan d' |title=Elemente, anorganische Verbindungen und Materialien |last2=Ans |first2=Jan d' |date=1998 |publisher=Verlag nicht ermittelbar |isbn=978-3-540-60035-0 |edition=4., neubearb. u. rev. Aufl |series=Taschenbuch für Chemiker und Physiker / D'Ans |location=Ort nicht ermittelbar}} It has a trigonal crystal structure of the cadmium iodide type (polytype 2H){{Cite book |title=Moderne anorganische Chemie: mit CD-ROM |date=2007 |publisher=de Gruyter |isbn=978-3-11-019060-1 |editor-last=Riedel |editor-first=Erwin |edition=3. Aufl |location=Berlin |editor-last2=Alsfasser |editor-first2=Ralf}}{{ cite journal | title = Neutron Diffraction Investigation of the Magnetic Order in MnI2 | first1 = J. W. | last1 = Cable | first2 = M. K. | last2 = Wilkinson | first3 = E. O. | last3 = Wollan | first4 = W. C. | last4 = Koehler | journal = Phys. Rev. | volume = 125 | issue = 6 | pages = 1860-1864 | year = 1962 | doi = 10.1103/PhysRev.125.1860 }} with the space group P{{overline|3}}m1 (space group no. 164). It dissolves in water and decomposes. The tetrahydrate has a monoclinic crystal structure with the space group P21/c (No. 14).{{Cite journal |last=Moore |first=J. E. |last2=Abola |first2=J. E. |last3=Butera |first3=R. A. |date=1985-09-15 |title=Structure of manganese(II) iodide tetrahydrate, MnI2.4H2O |url=https://scripts.iucr.org/cgi-bin/paper?S0108270185007466 |journal=Acta Crystallographica Section C: Crystal Structure Communications |language=en |volume=41 |issue=9 |pages=1284–1286 |doi=10.1107/S0108270185007466 |issn=0108-2701|url-access=subscription }}
Applications
It is often used in the lighting industry.
{{Cite book
| last = Cepanec
| first = Ivica
| author-link =
| publication-date =
| year = 2004
| title = Synthesis of Biaryls
| edition =
| volume =
| series =
| publication-place =
| place =
| publisher = Elsevier
| id =
| isbn = 0-08-044412-1
| doi =
| oclc =
| pages = 104
| url = https://books.google.com/books?id=UMLOo1wXWdwC&dq=%22Manganese(II)+bromide+%22&pg=PA104
| accessdate = 2008-06-18
}}
References
{{reflist}}
{{Manganese compounds}}
{{Iodides}}
{{DEFAULTSORT:Manganese(Ii) Iodide}}