Heterometallic Tetranuclear [LnIII2CoIII2] Complexes Including Suppression of Quantum Tunneling of Magnetization in the [DyIII2CoIII2] Single Molecule Magnet

摘要: Using a heterometallic approach the synthesis, structures, and magnetic properties are reported for complexes [Ln(III)(2)Co(III)(2)(OMe)(2)(teaH)(2)(O(2)CPh)(4)(MeOH)(4)](NO(3))(2)·MeOH·H(2)O {Ln = Gd (1a), Tb (2a), Dy (3a)} [Ln(III)(2)Co(III)(2)(OMe)(2)(teaH)(2)(O(2)CPh)(4)(MeOH)(2)(NO(3))(2)]·MeOH·H(2)O (1b), (2b), (3b)}. Both compounds respective lanthanide ions found to be isolated within same crystal. Each Ln(III) dinuclear unit is incorporated diamagnetic Co(III)/organic ligand backbone utilizing triethanolamine benzoic acid as bridging ligands. Magnetic studies reveal an absence of any observable coupling interaction case. The analogue displays single molecule magnet (SMM) behavior with large energy barrier magnetization reversal 88.8 K, quantum tunneling (QTM) effectively suppressed because nonmagnetic exchange ground state molecule. Dilution complex into isostructural yttrium matrix allowed us determine aspects relaxation mechanism system.