Silicon disulfide is the

inorganic compound An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds⁠that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''. Inorgan ...

with the formula Si S₂. Like

silicon dioxide Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundan ...

, this material is

polymer A polymer () is a chemical substance, substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeat unit, repeating subunits derived from one or more species of monomers. Due to their br ...

ic, but it adopts a 1-dimensional structure quite different from the usual forms of SiO₂.

Synthesis, structure, and properties

The material is formed by heating silicon and sulfur or by the exchange reaction between SiO₂ and Al₂S₃. The material consists of chains of edge-shared

tetrahedra In geometry, a tetrahedron (: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular Face (geometry), faces, six straight Edge (geometry), edges, and four vertex (geometry), vertices. The tet ...

, -Si(μ-S)₂Si(μ-S)₂-. Like other silicon sulfur-compounds (e.g., bis(trimethylsilyl)sulfide) SiS₂ hydrolyzes readily to release H₂S. In liquid

ammonia Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pu ...

it is reported to form the imide Si(NH)₂ and NH₄SH, but a recent report has identified crystalline (NH₄)₂ iS₃(NH₃)�2NH₃ as a product which contains the tetrahedral thiosilicate anion, SiS₃(NH₃)^2-. Reaction with ethanol gives the

alkoxide In chemistry, an alkoxide is the conjugate base of an alcohol and therefore consists of an organic group bonded to a negatively charged oxygen atom. They are written as , where R is the organyl substituent. Alkoxides are strong bases and, whe ...

tetraethyl orthosilicate and H₂S. With bulky tert-butanol, alcoholysis gives tris(tert-butoxy)silanethiol: :3 (CH₃)₃COH + SiS₂ → CH₃)₃COsub>3SiSH + H₂S Reaction with

sodium sulfide Sodium sulfide is a chemical compound with the formula Na2 S, or more commonly its hydrate Na2S·9 H2O. Both the anhydrous and the hydrated salts are colorless solids, although technical grades of sodium sulfide are generally yellow to brick red ...

, magnesium sulfide and aluminum sulfide give thiosilicates. SiS₂ is claimed to occur in certain interstellar objects.

References

Inorganic silicon compounds Sulfides Inorganic polymers Dichalcogenides {{Inorganic-compound-stub