Ytterbium(II) bromide

Ytterbium(II) bromide is an inorganic compound with the chemical formula YbBr₂.

Ytterbium(II) bromide

Names
Other names Ytterbium dibromide
Identifiers
CAS Number	25502-05-0
3D model (JSmol)	Interactive image
ChemSpider	124564
PubChem CID	57376293
CompTox Dashboard (EPA)	DTXSID20948399
InChI InChI=1S/2BrH.Yb/h2*1H;/q;;+2/p-2 Key: JLLHSFOQJNVQCV-UHFFFAOYSA-L
SMILES [Yb+2].[Br-].[Br-]
Properties
Chemical formula	YbBr2
Molar mass	332.84
Appearance	pale yellow solid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Preparation

Ytterbium(II) bromide can be produced by the reduction reaction of ytterbium(III) bromide and hydrogen at 500~600 °C:^[1]

2 YbBr₃ + H₂ → 2 YbBr₂ + 2 HBr

The ammonia compound can be obtained by reacting metallic ytterbium and ammonium bromide in liquid ammonia at −78 °C. The ammonia compound can be decomposed in high vacuum at 200 °C to obtain ytterbium(II) bromide:^[1]

Yb + 2 NH₄Br → YbBr_₂ + 2 NH₃ + H₂

Ytterbium(II) bromide can also be prepared by vacuum reduction of metallic ytterbium at 960 °C:^[2]

Yb + 2 YbBr₃ → 3 YbBr₂

Properties

Ytterbium(II) bromide is a light yellow solid and is highly hygroscopic. It can only be stored in an inert atmosphere or high vacuum. It is unstable in air or moisture and rapidly converts to the oxybromide and releases hydrogen gas. Ytterbium(II) bromide belongs to the orthorhombic crystal system, with SrI₂ structure and space group Pbca,^[3] or CaCl₂ structure and space group Pnnm. Its unit cell parameters are a=6.63 Å, b=6.93 Å, c=4.47Å.^[1][3]