Tris(2,2′‐bipyridyl‐N,N′)­nickel(II) thio­sulfate heptahydrate

The structure of the title compound, [Ni(C₁₀H₈­N₂)₃](S₂O₃)·7H₂O, consists of monomeric Ni(bipy)₃²⁺ cations embedded in an anionic network made up of S₂O₃^2? ions and hydration water mol­ecules. The structure presents the unusual feature of two neighbouring thio­sulfates approaching linearly head‐to‐head with an unusually short S?S contact distance of 3.25 Å.