Antimony triselenide

Antimony triselenide is the chemical compound with the formula Sb2Se3. The material exists as the sulfosalt mineral antimonselite, which crystallizes in an orthorhombic space group. In this compound, antimony is assigned the oxidation state 3+ and selenium 2-, but in fact the bonding in this compound is highly covalent as reflected by the black color and semiconducting properties of this and related materials.
It may be formed by the reaction of antimony with selenium.
References

^ Jambor, J. L.; Grew, E. S."New Mineral Names" American Mineralogist, Volume 79, pages 387-391, 1994.
^ Caracas, R.; Gonze, X. "First-principles study of the electronic properties of A2B3 minerals,, with A=Bi,Sb and B=S,Se, Note: Hypothetical sulphosalt structure derived from density functional theory"" Physics and Chemistry of Minerals 2005, volume 32 p
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