described by this idealized equation:

Alkali metal selenides react with selenium to form polyselenides, , which exist as chains and rings.

Other compounds

Tetraselenium tetranitride, Se₄N₄, is an explosive orange compound analogous to tetrasulfur tetranitride (S₄N₄). It can be synthesized by the reaction of selenium tetrachloride (SeCl₄) with {{chem.