Iridium(II) chloride

Iridium(II) chloride is an inorganic chemical compound of iridium metal and chlorine with the chemical formula IrCl₂.^[1][2] This is a metal salt of iridium and hydrochloric acid.

Iridium(II) chloride

Names
Other names Iridium dichloride, iridium bichloride
Identifiers
CAS Number	13465-17-3
3D model (JSmol)	Interactive image
InChI InChI=1S/2ClH.Ir/h2*1H;/q;;+2/p-2 Key: BBVIQHLJRNEBBW-UHFFFAOYSA-L
SMILES [Ir+2].[Cl-].[Cl-]
Properties
Chemical formula	Cl2Ir
Molar mass	263.12 g·mol−1
Appearance	dark-green crystals
Melting point	773 °C (1,423 °F; 1,046 K)
Solubility in water	Practically insoluble
Related compounds
Related compounds	Osmium(II) chloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis

• The substance is obtained by the interaction of powdered metallic iridium with chlorine gas when heated:^[3][4]

Ir + Cl₂ → IrCl₂

• Iridium(II) chloride can also be made in a reaction between iridium(III) chloride and metallic iridium:

2IrCl₃ + Ir → 3IrCl₂

Physical properties

Iridium dichloride forms shiny dark-green crystals that are practically insoluble in water.^[5] Poorly soluble in acids and alkali. When heated to 773 °C, IrCl₂ decomposes without melting.

The standard Gibbs energy of the formation of ΔG (298 K, kJ/mol) is -139.7.

Chemical properties

When heated to 773 °C decomposes according to the equation:^[6]

2IrCl₂ → 2IrCl + Cl₂

At temperatures above 798 °C, complete decomposition of the substance occurs:

IrCl₂ → Ir + Cl₂