Polyselenide

In chemistry, a polyselenide usually refers to anions of the formula (Sen)2-, where Se is the atomic symbol for the element selenium.

Instead, analogous to the preparation of many Zintl ions, polyselenides are produced by reduction of elemental Se with alkali metals.

[2] These reactions appear to proceed by initial formation of the alkali metal selenide, followed by the reaction of the latter with additional selenium: Once generated, alkali metal polyselenides can be converted to lipophilic salts by treatment cryptand ligands or by ion exchange with quat salts.

Polyselenides salts generally feature open chains, which adopt a zig-zag conformation.

[4] Polyselenides are prone to decomposition on exposure to air, in which case they are oxidized back to elemental selenium.