Barium iodide

Barium iodide is an inorganic compound with the formula BaI₂. The compound exists as an anhydrous and a hydrate (BaI₂(H₂O)₂), both of which are white solids. When heated, hydrated barium iodide converts to the anhydrous salt. The hydrated form is freely soluble in water, ethanol, and acetone.

Barium iodide^[1]

Names
IUPAC name Barium iodide
Other names Barium iodide, anhydrous
Identifiers
CAS Number	13718-50-8 (anhydrous) Y 7787-33-9 (dihydrate) N 13477-15-1 (hexahydrate) N
3D model (JSmol)	Interactive image Interactive image
ChemSpider	75507 Y
ECHA InfoCard	100.033.873
EC Number	237-276-9
PubChem CID	83684
UNII	WKC4T7680A Y
CompTox Dashboard (EPA)	DTXSID2065597
InChI InChI=1S/Ba.2HI/h;2*1H/q+2;;/p-2 Y Key: SGUXGJPBTNFBAD-UHFFFAOYSA-L Y InChI=1/Ba.2HI/h;2*1H/q+2;;/p-2 Key: SGUXGJPBTNFBAD-NUQVWONBAS
SMILES I[Ba]I [Ba+2].[I-].[I-]
Properties
Chemical formula	BaI2 (anhydrous) BaI2·2H2O (dihydrate)
Molar mass	391.136 g/mol (anhydrous) 427.167 g/mol (dihydrate)
Appearance	White orthorhombic crystals (anhydrous) colorless crystals (dihydrate)
Odor	odorless
Density	5.15 g/cm3 (anhydrous) 4.916 g/cm3 (dihydrate)
Melting point	711 °C (1,312 °F; 984 K) (anhydrous) decomposes at 740 °C (dihydrate)
Solubility in water	166.7 g/100 mL (0 °C) 221 g/100 mL (20 °C) 246.6 g/100 mL (70 °C)
Solubility	soluble in ethanol, acetone
Magnetic susceptibility (χ)	−124.0·10−6 cm3/mol
Structure
Crystal structure	PbCl2-type (Orthorhombic oP12)
Space group	Pnma (No. 62)
Thermochemistry
Std enthalpy of formation (ΔfH⦵298)	−602.1 kJ·mol−1
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	toxic
Related compounds
Other anions	barium fluoride barium chloride barium bromide
Other cations	beryllium iodide magnesium iodide calcium iodide strontium iodide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Structure

The structure of the anhydrous form resembles that of lead(II) chloride with each Ba center bound to nine iodide ligands^[2] and has a crystalline packing structure that is quite similar to BaCl₂.^[3]

Reactions

Anhydrous BaI₂ can be prepared by treating Ba metal with 1,2-diiodoethane in ether.^[4]

BaI₂ reacts with alkyl potassium compounds to form organobarium compounds.^[5]

BaI₂ can be reduced with lithium biphenyl, to give a highly active form of barium metal.^[6]

Safety

Like other soluble salts of barium, barium iodide is toxic.