Magnetic behaviour of octaethylporphyrinatomanganese(III) tetracyanoethenide, [MnOEP][TCNE], and hexacyanobutadienide, [MnOEP][C4(CN)6]: the importance of a uniform chain for stabilizing strong effective ferromagnetic coupling

Abstract

[MnOEP][A]{A=[TCNE]˙^– and [C₄(CN)₆]˙^–} have been isolated as extended 1D coordination polymers with trans-µ₂-[A] bridging ligands with strong {A=[C₄(CN)₆]˙^–} and weak {A =[TCNE]˙^–} ferromagnetic coupling as evidenced from the fit of the magnetic susceptibility to the Curie-Weiss law (θ= 5.1 and 67.1 K, respectively); the strong behaviour arises from the presence of uniform chains which are not present for the [TCNE]˙^– salt.