Synthesis, Structure, and Magnetic Properties of a Random Bimetallic One-dimensional Co^II-Mn^II Coordination Polymer with Mixed Azide-carboxylate Bridges

The 3d–3d random bimetallic compound [Co_2.28Mn_0.72(N₃)₆(mpc-3)₂(CH₃OH)₂] (1) (mpc-3 = N-methylpyridinium-3-carboxylate) was synthesized by partly substituting the Co^II ions in the homometallic compound by Mn^II. Complex 1 was structurally and magnetically characterized. It consists of one-dimensional chains with the neighboring metal ions being linked alternatively by [(μ-EO-N₃)₂(μ-COO)] (EO = end-on) triple bridges and double EO azide bridges. Hydrogen-bonding interactions and π–π interactions are involved in the formation of a three-dimensional supramolecular network. Magnetic measurements revealed that complex 1 exhibits slow relaxation, which is similar to the homometallic Co^II parent compound whereas the T_B is lower than that of the Co^II analog.