Tritellurium dichloride is the inorganic compound

Inorganic compound

Inorganic compounds have traditionally been considered to be of inanimate, non-biological origin. In contrast, organic compounds have an explicit biological origin. However, over the past century, the classification of inorganic vs organic compounds has become less important to scientists,...

 with the formula Te₃Cl₂

Chloride

The chloride ion is formed when the element chlorine, a halogen, picks up one electron to form an anion Cl−. The salts of hydrochloric acid HCl contain chloride ions and can also be called chlorides. The chloride ion, and its salts such as sodium chloride, are very soluble in water...

. It is one of the more stable lower chlorides of tellurium.

Preparation and properties

Te₃Cl₂ is a gray solid. Its structure consists of a chain of Te atoms (as in elemental Te), with every third Te center carrying two chloride ligands for the repeat uni -Te-Te-TeCl₂-. It is a semiconductor with a band gap of 1.52 eV, which is larger than that for elemental Te (0.34 eV). It is prepared by heating Te with the appropriate stoichiometry of chlorine.

Other lower tellurium chlorides

Te₂Cl₂ is a yellow liquid prepared by reaction of lithium polytellurides with TeCl₄. Te₂Cl, also a polymer, is a metastable gray solid, tending to convert to Te₃Cl₂ and TeCl₄. Being unstable with respect to disproportionation

Disproportionation

Disproportionation, also known as dismutation is used to describe a specific type of redox reaction in which a species is simultaneously reduced and oxidized so as to form two different products....

, tellurium dichloride has not been isolated as a solid, but has been characterised as the main component of the vapor formed with TeCl₄ and hot Te.