Exploring the Role of Intramolecular Interactions in the Suppression of Quantum Tunneling of the Magnetization in a 3d-4f Single-Molecule Magnet

Hydroxide-bridged Fe(4)(III)Ln(2)(III) clusters having the general formula [Fe(4)Ln(2)(mu(3)-OH)(2)(mdea)(6)(SCN)(2)(NO3)(2)(H2O)(2)]center dot 4H(2)O center dot 2MeCN {Ln = Y (1), Dy (2), mdea = N-methyldiethanolamine} were synthesized and magnetically characterized. The thermal relaxation of the magnetization for 2 and the diluted (Fe4DyYIII)-Dy-III-Y-III complex 3 (with and without applied field) has been analyzed. The diluted sample shows a dominant QTM at low temperatures that can be removed with a 0.15 T dc field. Both 2 and 3 show moderately high U-eff barriers and exhibit hysteresis loops until 5 K.

Automated summary

The study synthesized hydroxide-bridged Fe(4)(III)Ln(2)(III) clusters and characterized their magnetic properties. The diluted sample exhibited dominant quantum tunneling at low temperatures, which can be removed gradually with a dc field. Both cluster solid samples showed moderately high energy barriers and hysteresis loops at 5 K.