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| Names | |
|---|---|
| IUPAC name Iron(II) bromide | |
| Other names Ferrous bromide | |
| Identifiers | |
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3D model (JSmol) |
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| ChemSpider |
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| ECHA InfoCard | 100.029.244 |
| UNII | |
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| Properties | |
| FeBr2 | |
| Molar mass | 215.65 g mol−1 |
| Appearance | yellow-brown solid |
| Density | 4.63 g cm−3, solid |
| Melting point | 684 °C (1,263 °F; 957 K) (anhydrous) 27 °C (Hexahydrate) |
| Boiling point | 934 °C (1,713 °F; 1,207 K) |
| 117 g / 100 ml | |
| Solubility in other solvents | THF,methanol,ethanol |
| +13,600·10−6 cm3/mol | |
| Structure | |
| Rhombohedral,hP3, SpaceGroup = P-3m1, No. 164 | |
| octahedral | |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards | none |
| Related compounds | |
Otheranions | Iron(II) fluoride Iron(II) chloride Iron(II) iodide |
Othercations | Manganese(II) bromide Cobalt(II) bromide |
Related compounds | Vanadium(II) bromide Iron(III) bromide |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Iron(II) bromide refers toinorganic compounds with the chemical formula FeBr2(H2O)x. The anhydrous compound (x = 0) is a yellow or brownish-colored paramagnetic solid. Thetetrahydrate is also known, all being pale colored solids. They are common precursor to other iron compounds.
Like mostmetal halides, FeBr2 adopts a polymeric structure consisting of isolated metal centers cross-linked with halides. It crystallizes with theCdI2 structure, featuring close-packed layers of bromide ions, between which are located Fe(II) ions in octahedral holes.[1] The packing of the halides is slightly different from that for FeCl2, which adopts the CdCl2 motif. The tetrahydrates FeX2(H2O)4 (X = Cl, Br) have similar structures, with octahedral metal centers and mutually trans halides.[2]
FeBr2 is synthesized using amethanol solution of concentratedhydrobromic acid and iron powder. It adds the methanol solvate [Fe(MeOH)6]Br2 together with hydrogen gas. Heating the methanol complex in a vacuum gives pure FeBr2.[3]
FeBr2 reacts with two equivalents oftetraethylammonium bromide to give [(C2H5)4N]2FeBr4.[4] FeBr2 reacts with bromide and bromine to form the intensely colored, mixed-valence species [FeBr3Br9]−.[5]
FeBr2 possesses a strongmetamagnetism at 4.2 K and has long been studied as a prototypical metamagnetic compound.[6][7]
