The title compound, C18H24N2Se3, consists of discrete molecules; owing to the presence of strong intramolecular N⋯ Se interactions [N⋯ Se= 2.671 (4) and 2.873 (4) Å], the chalcogen Se atoms of the angular Se3 chain exhibit different coordination geometries, ie the terminal Se atoms are tricoordinated and exhibit a T-shaped environment of the CNSe2 core [N⋯ Se—Se= 173.73 (9) and 172.29 (9)°], while the central Se atom is dicoordinated ...