A family of 3d metal clusters based on N-N single bonds bridged quasi-linear trinuclear cores: the Mn analogue displaying single-molecule magnet behavior.

ABSTRACT: The reactions of the diacylhydrazine ligands N,N'-bisalicyl-2,6-pyridine dicarbohydrazide (H₆sphz) and N,N'-bis(3-methoxysalicyl)-2,6-pyridine dicarbohydrazide (H₆msphz) with various 3d metal salts, afforded a series of coordination clusters, namely, [Mn^III ₂Mn^II(sphz)(acac)₂(CH₃OH)₄] (1, acac^- = acetylacetone anions), [Ni^II ₃(msphz)(Py)₄] (2, Py = pyridine), [Cu^II ₆(sphz)₂(Py)₄] (3) and [Cu^II ₆(msphz)₂(Py)₄]·2DMF·2H₂O (4). Cluster 1 and 2 are single ligand assembled quasi-linear trinuclear structures. Both 3 and 4 consist a pair of quasi-linear {Cu₃} cores, which are linked together by two crossed ligands. The adjacent 3d metal ions in all trinuclear cores of 1-4 are bridged by N-N single bonds of ligands, which convey ferromagnetic (FM) interactions between 3d metal centers of 1, and antiferromagnetic (AFM) interactions between those of 2-4. In particular, the FM interactions and linear arrangement of mixed-valence Mn centers in 1 result in a large spin ground states value (S _T) of 13/2, as well as single-molecule magnet (SMM) behavior of slow relaxation and hysteresis of magnetization.

SUBMITTER: Wang K 

PROVIDER: S-EPMC9078267 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature