Thulium(II) iodide

Thulium(II) iodide is an inorganic compound with the chemical formula TmI₂.

Thulium(II) iodide

Names
Other names Thulium diiodide
Identifiers
CAS Number	60864-26-8 Y
3D model (JSmol)	Interactive image
ChemSpider	4401179
ECHA InfoCard	100.151.436
EC Number	622-686-6
PubChem CID	5231385
CompTox Dashboard (EPA)	DTXSID40411818
InChI InChI=1S/2HI.Tm/h2*1H;/q;;+2/p-2 Key: XGGRJQVPUOEAEU-UHFFFAOYSA-L
SMILES I[Tm]I
Properties
Chemical formula	I2Tm
Molar mass	422.74316 g·mol−1
Appearance	Dark brown hexagonal crystals
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Preparation and properties

Thulium(II) iodide can be obtained by reacting thulium(III) iodide and alkali metals in a tantalum container at 700~800°C. TmI₂ can be obtained by using lithium and sodium as reducing agents, while potassium, rubidium and caesium can generate the perovskite structure MTmI₃. TmI₂ can also react directly with CsI (340 °C) to generate CsTmI₃.

Thulium(II) iodide can also be prepared by reacting thulium and mercury(I) iodide. The reaction process is as follows:

2 Tm + 3 HgI₂ → 2 TmI₃ + 3 Hg

Tm + HgI₂ → TmI₂ + Hg

Tm + 2 TmI₃ → 3 TmI₂