catena-Poly[[nickel(II)-μ(3)-1,1-dicyano­ethene-2,2-dithiol­ato-κ(4) S,S′:N:N′-bis­[(15-crown-5)magnesium(II)]-μ(3)-1,1-dicyano­ethene-2,2-dithiol­ato-κ(4) N:N′:S,S′] dichloride]

The reaction of MgCl(2), NiCl(2), and Na(2)(i-mnt) (i-mnt is 1,1-dicyano­thene-2,2-dithiol­ate) with 15-crown-5 (15-C-5) leads to an infinite chain polymer, {[NiMg(2)(C(4)N(2)S(2))(2)(C(10)H(20)O(5))(2)]Cl(2)}(n) or {[Mg(15-C-5)](2)[Ni(i-mnt)(2)]Cl(2)}(n), which consists of two [Mg(15-C-5)](2+) complex cations, one [Ni(i-mnt)(2)](2−) complex anion and two Cl(−) ions per formula unit. In the [Ni(i-mnt)(2)](2−) complex anion, Ni(2+) is located on a crystallographic mirror plane with a slightly distorted square-planar coordination by four S atoms. In the [Mg(15-C-5)](2+) complex cations, the Mg and one O atom of the crown lie on mirror planes and the Mg atoms are in sevenfold coordination environments of five O atoms from the crown and two N atoms from two i-mnt anions. The bridging of the two complexes via the Mg—N bonds leads to the formation of one-dimensional chains along the a axis.