Ferromagnetic interactions in 0D and 2D Mn(II) coordination complexes containing nitronyl-nitroxide radicals and dicyanamide anions:: MnII(NITpPy)2[N(CN)2]2(H2O)2 and MnII(NITpPy)2[N(CN)2]2•2 CH3CN

Two new NITpPy manganese complexes, of formulae Mn(NITpPy)(2)[N(CN)(2)](2)(H2O)(2) (1) and Mn(NITpPy)(2)[N(CN)(2)](2). 2CH(3)CN (2), whereNITpPy stands for 2-(4-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxy-3-oxide, were synthesised and structurally and magnetically characterised. Compound 1 crystallises in the triclinic space group P(1) over bar (#2). The Mn atom is in a distorted octahedral geometry, where the [N(CN)(2)](-) ligands present mu (1) coordination sphere being completed by two water molecules and two NIRpPy units. Compound 2 crystallises in the orthorhimbic space group Cmca (#64). In this compound, the [Mn(NITpPy)(2)](2+) units are linked through mu (2) [N(CN)(2)](-) bridging ligands yielding a two dimensional polymeric structure. In both compounds (1) and (2), ferromagnetic interactions are observed but antiferromagnetic interactions dominate at very low temperature. (C) Academie des sciences. Editions scientifiques et medicales Elsevier SAS.