Osmium(III) chloride

Osmium(III) chloride
Names
	Other names Trichloroosmium; Osmium trichloride;
Identifiers
CAS Number	13444-93-4 anhydrous; 14996-60-2 trihydrate;
3D model (JSmol)	Interactive image;
ChemSpider	75306;
ECHA InfoCard	100.033.247
EC Number	236-587-7;
PubChem CID	83468;
CompTox Dashboard (EPA)	3065457;
	InChI InChI=1S/3ClH.Os/h3*1H;/q;;;+3/p-3 Key: UAIHPMFLFVHDIN-UHFFFAOYSA-K;
	SMILES Cl[Os](Cl)Cl;
Properties
Chemical formula	Cl3Os
Molar mass	296.58 g·mol−1
Appearance	dark gray solid (anhydrous); black crystals (hydrate)
Melting point	>500 °C (decomposes)
Solubility in water	insoluble
Solubility	soluble in nitric acid
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H301, H302, H311, H312, H314, H331, H332
Precautionary statements	P260, P262, P264, P264+P265, P270, P271, P280, P301+P316, P301+P317, P301+P330+P331, P302+P352, P302+P361+P354, P304+P340, P305+P354+P338, P316, P317, P321, P330, P361+P364, P362+P364, P363, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Osmium(III) chloride is an inorganic compound of osmium and chlorine with the chemical formula OsCl₃.^[3]

Synthesis

Osmium(III) chloride can be prepared by treating osmium with chlorine:

2Os + 3Cl₂ → 2OsCl₃

It can also be prepared by the decomposition of osmium(IV) chloride:

2OsCl₄ → 2OsCl₃ + Cl₂

Osmium(III) chloride hydrate is a precursor for the production of dichlorodihydridoosmium complexes and other compounds.^[4]

It is the precursor to a variety of arene complexes.^[5]

^ Perry, Dale L. (2016-04-19). Handbook of Inorganic Compounds. CRC Press. p. 303. ISBN 978-1-4398-1462-8.
^ PubChem. "Osmium chloride (OsCl3)". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-01-30.
^ Lide, David R. (19 June 2003). 1998 Freshman Achievement Award. CRC Press. p. 4-79. ISBN 978-0-8493-0594-8. Retrieved 31 March 2023.
^ "Osmium(III) chloride hydrate". Sigma Aldrich. Retrieved 31 March 2023.
^ Bell, Andrew G.; Koźmiński, Wiktor; Linden, Anthony; von Philipsborn, Wolfgang (1996). "¹⁸⁷Os NMR Study of (η⁶-Arene)osmium(II) Complexes: Separation of Electronic and Steric Ligand Effects". Organometallics. 15 (14): 3124–3135. doi:10.1021/om960053i.