Iridium(III) chloride

Iridium(III) chloride
	; α-IrCl3
	; β-IrCl3
	; hydrated iridium trichloride
Names
	Other names Iridium trichloride
Identifiers
CAS Number	10025-83-9 (anhydrous) ; 14996-61-3 (hydrate);
3D model (JSmol)	Interactive image;
ChemSpider	23837 ;
ECHA InfoCard	100.030.028
EC Number	233-044-6;
PubChem CID	82301;
UNII	20278OEG45 ;
CompTox Dashboard (EPA)	DTXSID10275787 ;
	InChI InChI=1S/3ClH.Ir/h3*1H;/q;;;+3/p-3 Key: DANYXEHCMQHDNX-UHFFFAOYSA-K;
	SMILES [Cl-].[Cl-].[Cl-].[Ir+3];
Properties
Chemical formula	IrCl3
Molar mass	298.58 g/mol (anhydrous)
Appearance	dark green solid; hygroscopic
Density	5.30 g/cm3, solid
Melting point	763 °C (1,405 °F; 1,036 K) (decomposes)
Solubility in water	insoluble (anhydrous IrCl3), soluble (hydrated derivative)
Magnetic susceptibility (χ)	−14.4·10−6 cm3/mol
Structure
Crystal structure	Monoclinic, mS16
Space group	C12/m1, No. 12
Thermochemistry
Std enthalpy of; formation (ΔfH⦵298)	-257 kJ/mol
Hazards
	GHS labelling:[1]
Pictograms
Signal word	Warning
Hazard statements	H302, H411
Flash point	non-flammable
Related compounds
Other cations	Rhodium(III) chloride
Related compounds	Platinum(II) chloride
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Iridium(III) chloride is the inorganic compound with the formula IrCl₃. The anhydrous compound is relatively rare, but the related hydrate is useful for preparing other iridium compounds. The anhydrous salt is a dark green crystalline solid. More commonly encountered is the trihydrate IrCl₃(H₂O)₃.

Preparation

Iridium is separated from the other platinum group metals as crystalline ammonium hexachloroiridate, (NH₄)₂[IrCl₆], which can be reduced to iridium metal in a stream of hydrogen. The spongy Ir thus produced reacts with chlorine at 300–400 °C to give iridium(III) chloride.

Hydrated iridium trichloride is obtained by heating hydrated iridium(III) oxide with hydrochloric acid.

Structure

Like the related rhodium compound, IrCl₃ adopts the structure seen for aluminium chloride.[2] This is the monoclinic α polymorph.[3] A rhombohedral β polymorph also exists. Both polymorphs have effectively the same anion lattice but differ in the octahedral interstices the iridium ions occupy.[4]

Uses

Industrially, most iridium complexes are generated from ammonium hexachloroiridate or the related chloroiridic acid (H₂IrCl₆) as these salts are the most common commercial forms of iridium chlorides.

Hydrated iridium(III) chloride is used in the laboratory for the preparation of other iridium compounds such as Vaska's complex, trans-[IrCl(CO)(PPh₃)₂].[5] Alkene complexes such as cyclooctadiene iridium chloride dimer[6][7] and chlorobis(cyclooctene)iridium dimer[7][6] can also be prepared by heating the trichloride with the appropriate alkene in water/alcohol mixtures.

Safety

Iridium(III) chloride is not listed under Annex I of Directive 67/548/EEC, but is listed in the inventory of the Toxic Substances Control Act (TSCA).

References

"C&L Inventory". echa.europa.eu. Retrieved 23 December 2021.
Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
Brodersen, K.; Moers, F.; Schnering, H. G. (1965). "Zur Struktur des Iridium(III)- und des Ruthenium(III)-chlorids". Naturwissenschaften. 52 (9): 205–206. doi:10.1007/BF00626459. S2CID 43351743.
Meisel, A.; Leonhardt, G. (1965). "Die Kristallstruktur von β-Iridium(III)-Chlorid". Z. Anorg. Allg. Chem. 339 (1–2): 57–66. doi:10.1002/zaac.19653390109.
Vaska, L.; & DiLuzio, J. W. (1961) J. Am. Chem. Soc. 83:2784. Girolami, G.S.; Rauchfuss, T.B.; Angelici, R.J. (1999). Synthesis and Technique in Inorganic Chemistry (3rd Edn.). Sausalito:University Science Books.
Winkhaus, G.; & Singer, H. (1966). Iridium(I)-Olefinkomplexe. Chem. Ber. 99:3610–18.
Herde, J. L.; Lambert, J. C.; & Senoff, C. V. (1974). Cyclooctene and 1,5-Cyclooctadiene Complexes of Iridium(I). Inorg. Synth. 1974, volume 15, pages 18–20. doi:10.1002/9780470132463.ch5.

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.

[1] "C&L Inventory". echa.europa.eu. Retrieved 23 December 2021.

[2] Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.

[3] Brodersen, K.; Moers, F.; Schnering, H. G. (1965). "Zur Struktur des Iridium(III)- und des Ruthenium(III)-chlorids". Naturwissenschaften. 52 (9): 205–206. doi:10.1007/BF00626459. S2CID 43351743.

[4] Meisel, A.; Leonhardt, G. (1965). "Die Kristallstruktur von β-Iridium(III)-Chlorid". Z. Anorg. Allg. Chem. 339 (1–2): 57–66. doi:10.1002/zaac.19653390109.

[5] Vaska, L.; & DiLuzio, J. W. (1961) J. Am. Chem. Soc. 83:2784. Girolami, G.S.; Rauchfuss, T.B.; Angelici, R.J. (1999). Synthesis and Technique in Inorganic Chemistry (3rd Edn.). Sausalito:University Science Books.

[winkhaus-6] Winkhaus, G.; & Singer, H. (1966). Iridium(I)-Olefinkomplexe. Chem. Ber. 99:3610–18.

[senoffcod-7] Herde, J. L.; Lambert, J. C.; & Senoff, C. V. (1974). Cyclooctene and 1,5-Cyclooctadiene Complexes of Iridium(I). Inorg. Synth. 1974, volume 15, pages 18–20. doi:10.1002/9780470132463.ch5.