Two Metal–Organic Frameworks Based on Hexanuclear Cobalt–Hydroxyl Clusters or a Manganese–Hydroxyl Chain from Triangular [M^II₃(μ₃-OH)] (M = Co and Mn) Units: Antiferromagnetic and Spin-Canting Antiferromagnetic Ordering with Soft-Magnetic Behavior

Abstract

Three-dimensional highly connected isonicotinic acid–base metal–organic frameworks (MOFs), [CoII6(μ3-OH)2(in)7(HCOO)3H2O]·4DMF (1) and [MnII3(μ3-OH)(in)3(CH3COO)2] (2) (Hin = isonicotinic acid), have been successfully prepared. Compounds 1 and 2 were constructed from planar Co6 cluster SBUs or rare 1D manganese-hydroxyl chain SBUs, respectively. Both SBUs contain triangular MII3(OH) (M = Co and Mn) central units, which are connected by rare syn,anti,syn,anti- and syn,syn,anti-coordinated formic acid or acetic acid. Both compounds 1 and 2 have good thermal stability, while compound 2 also exhibits an extraordinarily high moisture stability. Magnetic studies demonstrate that 1 shows antiferromagnetic behavior, and 2 exhibits spin-canting antiferromagnetic ordering with soft-magnetic behavior.