A one dimensional coordination polymer composed of antiferromagnetically coupled disk-like [Mn 7 ] units

The synthesis, characterization by X-ray analysis and magnetic properties of a one dimensional coordination polymer {[Mn 7 (OH) 2 (dhap) 2 (N 3 ) 3 (MeCN) 4 (ClO 4 ) 2 ]·2(MeCN)·2(ClO 4 )} ∞ ( 1 ) are reported. The ligand dhapH 4 in the complex is 2,6-bis[ N , N -di(hydroxyethyl)aminomethyl]pyridine. This compound crystallizes in the monoclinic space group C 2/ c . Each [Mn 7 (OH) 2 (dhap) 2 (N 3 ) 3 (MeCN) 4 (ClO 4 ) 2 ] unit (abbreviated by Mn 7 ) is linked end-to-end by azido ligands to its neighboring units to form a one dimensional polymer. Magnetic susceptibility measurements indicate that the polymer is composed of S = 8 units with inter-Mn 7 -unit antiferromagnetic coupling. The Jahn–Teller axes of the Mn 7 units are arranged in a zigzag manner along the polymer chain which induces spin canting at low temperatures. The slow magnetization relaxation at low temperatures was evidenced by observing out-of-phase signals in ac magnetic susceptibility measurements that give U eff = 47.5 K and Δ 0 = 2.7 × 10 −13 s. This phenomenon also indicates that this one dimensional coordination polymer functions as a single-chain magnet (SCM).