Tungsten diarsenide

Tungsten diarsenide is an arsenide of tungsten with the chemical formula WAs₂. Other tungsten arsenides include tungsten triarsenide (WAs₃) and ditungsten triarsenide (W₂As₃).^[1][3]

Tungsten diarsenide

Identifiers
CAS Number	12006-39-2
3D model (JSmol)	Interactive image
InChI InChI=1S/2As.W Key: FPQIORWKRHXRSI-UHFFFAOYSA-N
SMILES [As]#[W]#[As]
Properties
Chemical formula	As2W
Molar mass	333.68 g·mol−1
Appearance	black solid[1]
Density	6.9 g·cm−3[1]
Solubility in water	practically insoluble[2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Preparation

Tungsten diarsenide can be produced by the direct reaction of tungsten and arsenic at 600 to 1000 °C. It can also be formed by the reaction of arsenic or arsine and tungsten hexachloride.^[1][2]

Properties

Tungsten diarsenide is a black solid. It forms crystals in the monoclinic crystal system with the same structure of molybdenum diarsenide. Tungsten diarsenide is insoluble in hydrofluoric acid, hydrochloric acid and alkaline aqueous solutions. It reacts with concentrated nitric acid and sulfuric acid.^[1] At high temperatures, tungsten diarsenide reacts with air to form tungsten trioxide and arsenic trioxide.^[2]