Manganese‐Octacyanidoniobate‐Based Ferrimagnet Possessing Bridging Ligands with Disulfide Bonds

• Published in: European journal of inorganic chemistry Vol. 2021; no. 45; pp. 4681 - 4689
• Main Authors: Kanno, Takefumi, Nakabayashi, Koji, Imoto, Kenta, Ohkoshi, Shin‐ichi
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 07.12.2021
• Subjects: Antiferromagnetism; Bridging ligand; Chemical bonds; Coordination; Critical temperature; Crystallography; Disulfide bonds; Ferrimagnet; Ferrimagnetism; Ferrimagnets; Inorganic chemistry; Ligands; Magnets; Manganese; Molecule-based magnet; Niobium; Octacyanometallates; Pyridines
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.202100747

We synthesized a cyanido‐bridged Mn−Nb metal assembly possessing large‐sized bridging ligands with disulfide bonds, [Mn(dpds)2]2[Nb(CN)8] ⋅ 6H2O (MnNb, dpds: 4,4’‐dipyridyldisulfide). MnNb has a three‐dimensional coordination framework in which the Mn and Nb sites are bridged by cyanides, while the Mn sites are combined by dpds ligands. The two crystallographically independent dpds ligands are bent around the disulfide bond with large C(pyridine)−S−S−C(pyridine) dihedral angles of 105.4(5)° and 102.2(5)°, respectively. For molecule‐based magnets, dpds is a relatively large bridging ligand, but it is compatible with the limited space of the cyanido‐bridged Mn−Nb coordination framework due to the bent structure. Additionally, antiferromagnetic coupling in MnNb of −13 cm−1 between MnII (S=5/2, g=2) and NbIV (S=1/2, g=2) induces ferrimagnetism with a critical temperature of 46 K. A three‐dimensional cyanido‐bridged Mn−Nb metal assembly possessing bridging ligands with disulfide bonds has been synthesized. The present compound shows ferrimagnetism with Tc of 46 K. Although the ligands with the disulfide bonds are significantly large in size, they are packed in the three‐dimensional cyanido‐bridged Mn−Nb framework due to the bent structure around the disulfide bond.