Related compounds Molar mass 306.22 g/mol Boiling point 53 °C Appearance yellow crystalline solid | Formula IrF6 Density 5.11 g/cm³ Melting point 44 °C | |
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Iridium hexafluoride, also iridium(VI) fluoride, (IrF6) is a compound of iridium and fluorine and one of the seventeen known binary hexafluorides. It is one of only a few compounds with iridium in the oxidation state +6.
Contents
Synthesis
Iridium hexafluoride is made by a direct reaction of iridium metal in an excess of elemental fluorine gas at 300 °C. However, it is thermally unstable and must be frozen out of the gaseous reaction mixture to avoid dissociation.
Ir + 3 F2 → IrF
6
Description
Iridium hexafluoride is a yellow crystalline solid that melts at 44 °C and boils at 53.6 °C. The solid structure measured at −140 °C is orthorhombic space group Pnma. Lattice parameters are a = 9.411 Å, b = 8.547 Å, and c = 4.952 Å. There are four formula units (in this case, discrete molecules) per unit cell, giving a density of 5.11 g·cm−3.
The IrF6 molecule itself (the form important for the liquid or gas phase) has octahedral molecular geometry, which has point group (Oh). The Ir–F bond length is 1.833 Å.