[Bis­(di­phenyl­phosphino)­alkane](pentane-2,4-di­thionato) complexes of nickel(II)

The structures of a series of four-coordinate nickel(II) complexes of the form [Ni(sacsac)L] PF₆ (sacsac = pentane-2,4-di­thione anion; L = (Ph₂P)₂(CH₂)_n, n = 1,2,3) have beendetermined. These are [bis­(di­phenyl­phosphino)­methane](pentane-2,4-di­thionato-S,S′)­nickel(II) hexa­fluoro­phosphate, [Ni(C₂₅H₂₂P₂)(C₅H₇S₂)]PF₆, [1,2-bis­(di­phenylphosphino)­ethane](pentane-2,4-di­thionato–S,S′)­nickel(II) hexa­fluoro­phosphate, [Ni(C₂₆H₂₄P₂)(C₅H₇S₂)]PF₆, and [1,3-bis­(di­phenyl­phosphino)­propane](pentane-2,4-di­thionato-S,S′)­nickel(II) hexa­fluoro­phosphate, [Ni(C₂₇H₂₆P₂)(C₅H₇S₂)]PF₆. All have a distorted square-planar arrangement about Ni with angles around Ni varying with the length of the hydro­carbon chain.