Nickel(II) iodide
Chemical compound
From Wikipedia, the free encyclopedia
Nickel(II) iodide is an inorganic compound with the formula NiI2. This paramagnetic black solid dissolves readily in water to give bluish-green solutions,[2] from which crystallizes the aquo complex [Ni(H2O)6]I2 (image above).[3] This bluish-green colour is typical of hydrated nickel(II) compounds. Nickel iodides find some applications in homogeneous catalysis.
Hexahydrate | |
-iodide-xtal-3D-SF.png) | |
| Names | |
|---|---|
| IUPAC name
Nickel(II) iodide | |
| Other names
Nickelous iodide | |
| Identifiers | |
3D model (JSmol) |
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| ChemSpider | |
| ECHA InfoCard | 100.033.319 |
| EC Number |
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PubChem CID |
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| UNII | |
CompTox Dashboard (EPA) |
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| Properties | |
| I2Ni | |
| Molar mass | 312.5023 g·mol−1 |
| Appearance | iron-black solid (anhydrous) bluish-green solid (hexahydrate) |
| Density | 5.384 g/cm3 |
| Melting point | 780 °C (1,440 °F; 1,050 K) (anhydrous) 43 °C (hexahydrate, loses water) |
| 124.2 g/100 mL (0 °C) 188.2 g/100 mL (100 °C) | |
| Solubility | alcohols |
| +3875.0·10−6 cm3/mol | |
| Hazards | |
| GHS labelling:[1] | |
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| Danger | |
| H317, H334, H341, H350i, H360D, H372, H410 | |
| P203, P233, P260, P264, P270, P271, P272, P273, P280, P284, P302+P352, P304+P340, P318, P319, P321, P333+P317, P342+P316, P362+P364, P391, P403, P405, P501 | |
| Related compounds | |
Other anions |
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Other cations |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Structure and synthesis
The anhydrous material crystallizes in the CdCl2 motif, featuring octahedral coordination geometry at each Ni(II) center. NiI2 is prepared by dehydration of the pentahydrate.[4]
NiI2 readily hydrates, and the hydrated form can be prepared by dissolution of nickel oxide, hydroxide, or carbonate in hydroiodic acid. The anhydrous form can be produced by treating powdered nickel with iodine.[5]
Applications
Catalysis
NiI2 has some industrial applications as a catalyst in carbonylation reactions.[6] It is also has niche uses as a reagent in organic synthesis, especially in conjunction with samarium(II) iodide.[7]
Like many nickel complexes, those derived from hydrated nickel iodide have been used in cross coupling.[8]
Spintronics
At 60 K (−213.2 °C; −351.7 °F) crystalline NiI2 exhibits p-wave magnetism, in which the spins of nickel atoms became arranged in a spiral pattern in two orientations. The orientations can be switched via a small electrical current. If it can be applied in digital devices, this spintronics behavior requires far less current than the conventional charge-based electronics that powers devices such as computers and phones.[9]