| Names | |
|---|---|
| Other names  Arsenic(III) selenide  | |
| Identifiers | |
3D model (JSmol)  | |
| ChemSpider | |
| ECHA InfoCard | 100.013.745 | 
| EC Number | 
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 PubChem CID  | |
| RTECS number | 
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| UNII | |
 CompTox Dashboard (EPA)  | |
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| Properties | |
| As2Se3 | |
| Molar mass | 386.756 g·mol−1 | 
| Appearance | brown-black powder [1] or metallic gray crystals | 
| Odor | odorless | 
| Density | 4.75 g/cm3 [1] | 
| Melting point | 377 °C (711 °F; 650 K) [1] | 
| insoluble [1] | |
| Structure [2] | |
| Monoclinic, mP20 | |
| P21/c, No. 14 | |
a = 0.43 nm, b = 0.994 nm, c = 1.29058 nm α = 90°, β = 109.927°, γ = 90°  | |
 Formula units (Z)  | 4 | 
| Hazards | |
| GHS labelling: | |
|   | |
| Danger | |
| H301, H330, H331, H373, H410 | |
| P260, P261, P264, P270, P271, P273, P284, P301+P310, P304+P340, P310, P311, P314, P320, P321, P330, P391, P403+P233, P405, P501 | |
| NFPA 704 (fire diamond) | |
| Related compounds | |
Other anions   | |
Other cations   | antimony(III) selenide | 
Related compounds  | arsenic(V) selenide | 
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).  | |
Arsenic triselenide is an inorganic chemical compound with the chemical formula As 2 Se 3.
Amorphous arsenic triselenide is used as a chalcogenide glass for infrared optics. When purified, it transmits light with wavelengths between ca. 0.7 and 19 μm. [3]
In arsenic triselenide, arsenic is covalently bonded to selenium, where arsenic has a formal oxidation state of +3, and selenium −2.
Thin film selenide glasses have emerged as an important material for integrated photonics due to its high refractive index, mid-IR transparency and high non-linear optical indices. High-quality As2Se3 glass films can be deposited from spin coating method from ethylenediamine solutions. [4]