Uranium disulfide
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| Section1 = {{Chembox Identifiers
| CASNo = 12039-14-4
| PubChem = 131700999
| StdInChI=1S/2S.U/q2*-2;+4
| StdInChIKey = OYHHCKFHGQELGK-UHFFFAOYSA-N
| SMILES = [S-2].[S-2].[U+4]
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| Section2 = {{Chembox Properties
| Formula = US2
| MolarMass = 302.160 g/mol
| Appearance = Black crystals
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| Section3 = {{Chembox Structure
| CrystalStruct = Tetragonal (α-US2)
| SpaceGroup = P4/ncc (No. 130)
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| LattConst_a = 1029.3 pm
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| LattConst_c = 637.4 pm
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Uranium disulfide is an inorganic chemical compound of uranium in oxidation state +4 and sulfur in oxidation state −2. It is radioactive and appears in the form of black crystals.
Uranium disulfide has two allotropic forms: α-uranium disulfide, which is stable above the transition temperature (about 1350 °C) and metastable below it, and β-uranium disulfide which is stable below this temperature. The tetragonal crystal structure of α-US2 is identical to α-USe2.
Uranium disulfide can be synthesized by reduction of gaseous hydrogen sulfide with uranium metal powder at elevated temperatures.