Iridium hexafluoride
-fluoride.svg) | |
| Names | |
|---|---|
| IUPAC name
iridium(VI) fluoride | |
| Other names
iridium hexafluoride | |
| Identifiers | |
3D model (JSmol) |
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| ChemSpider | |
| ECHA InfoCard | 100.029.113 |
PubChem CID |
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| UNII | |
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| Properties | |
| IrF6 | |
| Molar mass | 306.22 g/mol |
| Appearance | yellow crystalline solid[1] |
| Density | 5.11g/mL[2] |
| Melting point | 44 °C (111 °F; 317 K)[1] |
| Boiling point | 53.6 °C (128.5 °F; 326.8 K)[1] |
| Solubility | soluble in HF |
| Hazards | |
| GHS labelling:[3] | |
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| Danger | |
| H290, H314 | |
| P234, P260, P264, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P321, P363, P390, P405, P501 | |
| Related compounds | |
Other cations |
rhodium hexafluoride osmium hexafluoride platinum hexafluoride |
Related compounds |
iridium(V) fluoride |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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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.
Synthesis
[edit]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 F
2 → IrF
6
Description
[edit]Iridium hexafluoride is a yellow crystalline solid that melts at 44 °C and boils at 53.6 °C.[1] 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.[2]
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.[2]
Calculations suggest that fluorine might react with iridium hexafluoride at 39 GPa to form IrF8.[4]
It is able to oxidize elemental chlorine to the blue-colored salt Cl
4IrF
6 (containing Cl4+, originally misidentified as Cl2+), in a process somewhat analogous to the oxidation of elemental oxygen by PtF6 (which yields the O2+ containing O
2PtF
6).[5][6]
References
[edit]- 1 2 3 4 CRC Handbook of Chemistry and Physics, 90th Edition, CRC Press, Boca Raton, Florida, 2009, ISBN 978-1-4200-9084-0, Section 4, Physical Constants of Inorganic Compounds, p. 4-85.
- 1 2 3 Drews, T.; Supeł, J.; Hagenbach, A.; Seppelt, K. (May 2006). "Solid State Molecular Structures of Transition Metal Hexafluorides". Inorganic Chemistry. 45 (9): 3782–8. doi:10.1021/ic052029f. PMID 16634614.
- ↑ PubChem. "Iridium hexafluoride". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-04-06.
- ↑ Lin, Jianyan; Zhao, Ziyuan; Liu, Chunyu; Zhang, Jing; Du, Xin; Yang, Guochun; Ma, Yanming (2019-03-13). "IrF8 Molecular Crystal under High Pressure". Journal of the American Chemical Society. 141 (13). American Chemical Society (ACS): 5409–5414. doi:10.1021/jacs.9b00069. ISSN 0002-7863. PMID 30864432. S2CID 76664353.
- ↑ Seidel, Stefan; Seppelt, Konrad (2000-11-03). "The Cl4+ Ion". Angewandte Chemie. 39 (21): 3923–3925. doi:10.1002/1521-3773(20001103)39:21<3923::AID-ANIE3923>3.0.CO;2-Y.
- ↑ Graham, Lionell (1978-10-01). The Oxidizing Power of Some Platinum Metal Fluorides (PDF) (PhD thesis). Lawrence Berkeley National Laboratory. p. 55. Archived from the original (PDF) on 2024-09-16. Retrieved 2026-01-21.
Further reading
[edit]- Gmelins Handbuch der anorganischen Chemie, System Nr. 67, Iridium, Supplement Volume 2, pp. 99–102.