Structure and characterisation of [Pt(Me2pipdt)2][Pt(mnt)2]2 and its unusual magnetic properties associated with a non-regular one-dimensional [Pt(mnt)2] stack

Abstract For electro-oxidation of [Pt(Me 2 pipdt) 2 ][Pt(mnt) 2 ] (Me 2 pipdt N , N ′-dimethyl-piperazine-2,3-dithione; mnt = maleonitrile-2,3-dithiolate) ( 1a ) the novel salt [Pt(Me 2 pipdt) 2 ][Pt(mnt) 2 ] 2 ( 2a ) has been prepared and characterised. 2a exhibits segregated chains of anionic and cationic complexes. The anions generate a non-regular stack with the separation between the planes of 3.558(5) A [3.60(1) A is the Pt⋯C C (mid point) separation] and 3.643(5) A [3.980(3) A is the separation between Pt and S-atoms]. The cations are perpendicular to the anions and interposed between those stacks in a ribbon fashion. Magnetic measurements show the presence of a magnetic transition between the behaviour of an antiferromagnetic alternating-exchange chain and the behaviour of a set of antiferromagnetic dimers.