Rhenium(III) iodide

Rhenium(III) iodide is a binary chemical compound of rhenium and iodide with the chemical formula ReI
₃.^[1][2]

Rhenium(III) iodide

Names
Other names Rhenium(III) iodide, triiodorhenium
Identifiers
CAS Number	15622-42-1
3D model (JSmol)	Interactive image
ChemSpider	21170009
ECHA InfoCard	100.036.074
EC Number	239-698-9
PubChem CID	12984320
CompTox Dashboard (EPA)	DTXSID60275813
InChI InChI=1S/3HI.Re/h3*1H;/q;;;+3/p-3 Key: DDMQJDMHHOTHKW-UHFFFAOYSA-K
SMILES I[Re](I)I
Properties
Chemical formula	I3Re
Molar mass	566.920 g·mol−1
Appearance	violet-black crystals
Density	6.37 g/cm3
Melting point	800 °C (1,470 °F; 1,070 K)
Solubility in water	poorly soluble
Structure
Crystal structure	monoclinic
Related compounds
Related compounds	Iridium triiodide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis

Rhenium(III) iodide can be synthesized by the decomposition of rhenium(IV) iodide:^[3][4]

2ReI₄ → 2ReI₃ + I₂

Another way to make it is by introduction of ethanol into a mixture of perrhenic acid and hydroiodic acid.

HReO₄ + 3HI + 2C₂H₅OH → ReI₃ + 4H₂O + 2CH₃CHO

Physical properties

Rhenium(III) iodide forms violet-black crystals. It is poorly soluble in water, acetone, ethanol, ether, and dilute acid solutions.

Chemical properties

When heated in vacuum up to 170 °C, the compound decomposes to rhenium(II) iodide, and at 380 °C — to rhenium(I) iodide:

2ReI₃ → 2ReI₂ + I₂

ReI₃ → ReI + I₂