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
3D model (JSmol)
  • InChI=1S/2ClH.Ir/h2*1H;/q;;+2/p-2
    Key: BBVIQHLJRNEBBW-UHFFFAOYSA-L
  • [Ir+2].[Cl-].[Cl-]
Properties
Cl2Ir
Molar mass263.12 g·mol−1
Appearancedark-green crystals
Melting point773 °C (1,423 °F; 1,046 K)
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).

Synthesis

  • The substance is obtained by the interaction of powdered metallic iridium with chlorine gas when heated:[3][4]
Ir + Cl2 → IrCl2
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

References