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.