Gallium(III) iodide

Gallium(III) iodide is the inorganic compound with the formula GaI₃. A yellow hygroscopic solid, it is the most common iodide of gallium.^[3] In the chemical vapor transport method of growing crystals of gallium arsenide uses iodine as the transport agent. In the solid state, it exists as the dimer Ga₂I₆, with a diborane structure.^[4] When vaporized, its forms GaI₃ molecules of D_3h symmetry where the Ga–I distance is 2.458 Angstroms.^[5]

Gallium(III) iodide

Gallium(III) iodide
Names
Other names gallium triiodide
Identifiers
CAS Number	13450-91-4 N
3D model (JSmol)	Interactive image
ChemSpider	75316 Y
ECHA InfoCard	100.033.269
EC Number	236-611-6
PubChem CID	83478
CompTox Dashboard (EPA)	DTXSID7065467
InChI InChI=1S/Ga.3HI/h;3*1H/q+3;;;/p-3 Y Key: DWRNSCDYNYYYHT-UHFFFAOYSA-K Y InChI=1/Ga.3HI/h;3*1H/q+3;;;/p-3 Key: DWRNSCDYNYYYHT-DFZHHIFOAW
SMILES I[Ga](I)I
Properties
Chemical formula	GaI3
Molar mass	450.436 g/mol
Appearance	light yellow powder
Density	4.5 g/cm3[1]
Melting point	212 °C (414 °F; 485 K)[1]
Boiling point	340 °C (644 °F; 613 K)[1]
Solubility in water	decomposes
Magnetic susceptibility (χ)	−149.0·10−6 cm3/mol
Thermochemistry[2]
Heat capacity (C)	100 J/(mol·K)
Std molar entropy (S⦵298)	205.0 J/(mol·K)
Std enthalpy of formation (ΔfH⦵298)	−238.9 kJ/mol
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H314, H317, H334, H335, H361
Precautionary statements	P280, P305+P351+P338, P310
NFPA 704 (fire diamond)	4 0 1
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

Gallium triiodide can be reduced with gallium metal to give a green-colored gallium(I) iodide. The nature of this species is unclear, but it is useful for the preparation of gallium(I) and gallium(II) compounds.^[6][7]

See also

• Gallium halides