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), [Co II 6 (μ 3 -OH) 2 (in) 7 (HCOO) 3 H 2 O]•4DMF (1) and [Mn II 3 (μ 3 -OH)-(in) 3 (CH 3 COO) 2 ] (2) (Hin = isonicotinic acid), have been successfully prepared. Compounds 1 and 2 were constructed from planar Co 6 cluster SBUs or rare 1D manganese-hydroxyl chain SBUs, respectively. Both SBUs contain triangular M II 3 (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.

Different Phenomena in Magnetic/Electrical Properties of Co(II) and Ni(II) Isomorphous MOFs

“…where the best parameters are J 1 /k B = 2.01(9), J 2 /k B = 0.18(6), g = 2.10, and zJ′/k B = −0.72 (8). It is important to note that the resulting g value is very much in line with the Ni(II) compound.…”

“…Metal–organic frameworks (MOFs) have attracted much attention as a functional material in recent years. This is not only because of their intriguing structures but also because of their potential applications in the fields of luminescence, catalysis, adsorption, proton conduction, and so on. − In particular, MOFs are excellent candidates to study the elusive magnetostructural correlations and some fundamental magnetic phenomena, such as spin-canting, spin-frustration, metamagnetism, single-molecule magnets, and so on. − …”

Hierarchical Construction and Magnetic Difference of {Co12M12} (M = Co2+/Cd2+) Aggregates from {Co14} Cluster-Based Precursors in the Presence of Homo/Heterometal Salts

“…This markedly field-dependent behavior is typical for spin-canting. 36,37 Comparing {Co 24 } to {Co 14 } and {Co 12 Cd 12 }, we found that the magnetic behavior of {Co 24 } was more markedly field-dependent than {Co 14 }, suggesting the local spin-canting configuration in {Co 24 }. While external Co 2+ was replaced by Cd 2+ , the canted behavior had been suppressed.…”