Supramolecular isomorphic dodecanuclear cobalt clusters with the same metal shell but different core ligands.

In this work, we report two supramolecular isomorphic dodecanuclear cobalt complexes, [Co 12 ( mtz ) 3 (L) 6 (NO 3 ) 2 (OH)(N 3 ) 3 ]·(OH) 3 (1) and [Co 12 ( mtz ) 3 (L) 6 (NO 3 ) 2 (OH)(N 3 )(OAc)]·(OH) 4 (2), (H mtz = 5-methyl-1 H -tetrazole, H 2 L = 7,7'-(ethane-1,1-diyl) diquinolin-8-ol) crystallizing in the P̄ space group with the same unit cell parameters. In 1 and 2, two pirate hat-like hexanuclear Co 6 (NO 3 )(L) 3 units form the same dodecanuclear metal shell, but the ligands between the hexanuclear units as the core are distinct. The introduction of acetate anions leads to a blue shift of the absorption band in the visible region. Magnetism studies indicate an antiferromagnetic interaction between the Co II ions in the clusters.