Terbium(III) iodide

Terbium(III) iodide
Names
	Other names terbium triiodide
Identifiers
CAS Number	13813-40-6 ;
3D model (JSmol)	Interactive image;
ChemSpider	75569;
ECHA InfoCard	100.034.049
EC Number	237-469-8;
PubChem CID	83747;
CompTox Dashboard (EPA)	DTXSID0065644 ;
	InChI Key: OJXRJPFRTRETRN-UHFFFAOYSA-K; InChI=1S/3HI.Tb/h3*1H;/q;;;+3/p-3;
	SMILES I[Tb](I)I;
Properties
Chemical formula	TbI3
Molar mass	539.638 g/mol
Appearance	hygroscopic crystals
Density	5.2 g/cm3, solid
Melting point	957 °C (1,755 °F; 1,230 K)
Structure
Crystal structure	hexagonal
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H317, H361
Precautionary statements	P201, P202, P261, P264, P271, P272, P280, P281, P302+P352, P304+P340, P305+P351+P338, P308+P313, P312, P332+P313, P333+P313, P337+P313, P362, P363, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Terbium(III) iodide (Tb I₃) is an inorganic chemical compound.

Preparation

Terbium(III) iodide can be produced by reacting terbium and iodine.^[2]

2 Tb + 3 I₂ → 2 TbI₃

Terbium iodide hydrate can be crystallized from solution by reacting hydriodic acid with terbium, terbium(III) oxide, terbium hydroxide or terbium carbonate:

2 Tb + 6 HI → 2 TbI₃ + 3 H₂↑

Tb₂O₃ + 6 HI → 2 TbI₃ + 3 H₂O

2 Tb(OH)₃ + 6 HI → 2 TbI₃ + 3 H₂O

Tb₂(CO₃)₃ + 6 HI → 2 TbI₃ + 3 H₂O + 3 CO₂

An alternative method is reacting terbium and mercury(II) iodide at 500 °C.^[3]

Terbium(III) iodide adopts the bismuth(III) iodide (BiI₃) crystal structure type,^[4]^[3] with octahedral coordination of each Tb³⁺ ion by 6 iodide ions.^[5]