Iron(II) bromide

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Iron(II) bromide
Iron(II) bromide
IUPAC name
Iron(II) bromide
Other names
Ferrous bromide
7789-46-0 YesY
ChemSpider 74218 YesY
ECHA InfoCard 100.029.244
Jmol 3D model Interactive image
PubChem 659170
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)
Solubility in other solvents THF, methanol, ethanol
Rhombohedral, hP3, SpaceGroup = P-3m1, No. 164
Main hazards none
R-phrases R20 R36/37/38
S-phrases S26 S36
Related compounds
Other anions
Iron(II) chloride
Other cations
iron(III) bromide
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YesYN ?)
Infobox references

Iron(II) bromide is the chemical compound with the chemical formula FeBr2. The anhydrous compound is a yellow or brownish-colored paramagnetic solid. It is a common precursor to other iron compounds in research laboratory. Several hydrates of FeBr2 are also known.


Like most metal halides, FeBr2 adopts a polymeric structure consisting of isolated metal centers cross-linked with halides. It crystallizes with the CdI2 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.

Synthesis and reactions[edit]

FeBr2 is synthesized using a methanol solution of concentrated hydrobromic acid and iron powder. gives the methanol solvate [Fe(MeOH)6]Br2 together with hydrogen gas. Heating the methanol complex in a vacuum gives pure FeBr2.[2] Iron(II) bromide cannot be formed by the reaction of iron and bromine, because that reaction would produce ferric bromide.

FeBr2 reacts with 2 equivalents of (C2H5)4NBr to give [(C2H5)4N]2FeBr4.[3]

FeBr2 reacts with bromide and bromine to form the intensely colored, mixed-valence species [FeBr3Br9].[4]

FeBr2 is a weak reducing agent, as are all ferrous compounds.


  1. ^ Haberecht, J.; Borrmann, H.; Kniep, R. "Refinement of the Crystal Structure of Iron Dibromide, FeBr2" Zeitschrift für Kristallographie - New Crystal Structures 2001, vol. 216, p. 510. doi:10.1524/ncrs.2001.216.14.544
  2. ^ G. Winter, "Iron(II) Halides" "Inorganic Syntheses" 1973, volume 14, pages 101-104. doi: 10.1002/9780470132456.ch20
  3. ^ N. S. Gill, F.. B. Taylor Inorganic Syntheses 1967, volume 9, page 136-142. doi: 10.1002/9780470132401.ch37
  4. ^ Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5