Synthesis, Structure, and Magnetic Behavior of Two New 1D Polymeric Manganese Azido Complexes

Artikel i vetenskaplig tidskrift, 2006

Two new MnII one-dimensional compounds with formulae [Mn(μ-N3)2(pyzamid)2]n (1) and [Mn2(3-ampy)4(μ-N3)2(N3)2(H2O)2]n, (2) (pyzamid = pyrazineamide and 3-ampy = 3-aminopyridine) were structurally and magnetically characterized. Compound 1 crystallizes in the monoclinic system, P2/c space group, and polymerizes through double end-on azido bridges giving 1D chains with the MnII atoms in a MnN6 environment. Compound 2 crystallizes in the triclinic system, P-1 space group, and consists of alternate [Mn(3-ampy)2(μ-N3)2(N3)2] and [Mn(3-ampy)2(μ-N3)2(H2O)2] octahedrons (MnN6 - MnN4O2 environments), linked by single end-to-end azido bridges. Both chains show very uncommon topologies. Attemps to obtain manganese/azido derivatives with the qux = quinoline-4-carboxylato anion gave the recently reported compound [Mn(μ-qux)2(μ-H2O)]n (3), which consists of a chain with only carboxylato and aqua bridges with the MnII atoms in a MnO6 slightly distorted octahedron. In good agreement with the expected behavior, magnetic susceptibility measurements show weak ferromagnetic interactions for 1, whereas compound 2 exhibits moderate antiferromagnetic coupling.