Suppression of zero-field quantum tunneling of magnetization by a fluorido bridge for a very hard 3d-4f single-molecule magnet

Single-molecule magnets (SMMs) have been proposed for ultra-high-density information storage due to prolonged relaxation times below blocking temperature (T-B). However, many SMMs suffer from fast magnetization loss at zero-field regime due to the quantum tunneling of magnetization (QTM) effect. Here we show the creation of large ground magnetic momentum is crucial to suppress zero-field QTM for SMMs. The recipe is to use bridging fluoride, which creates ferromagnetic couplings among the lanthanide ions in the complex [Dy3Cr3(mu(3)-F) (mu(3)-OH)(3)(mdea)(3)(piv)(8)DMF]center dot H2O center dot CH3CN. As such, the molecule owns a large ground magnetic moment of 10:7 mu(B) and is confirmed to be an SMM with T-B of 5 K. More importantly, a very hard magnetic hysteresis loop with a coercive field of 1.3 T and more than 97% remanence is observed up to 0.7 K. Ab initio calculations fully support such observations, rendering the importance of fluorido bridge to suppress zero-field QTM for lanthanide-based SMMs.

Automated summary

This study demonstrates the importance of creating a large ground magnetic moment for suppressing the zero-field quantum tunneling of magnetization in single-molecule magnets (SMMs). By using bridging fluoride to create ferromagnetic couplings among the lanthanide ions, the molecule in this study possesses a large ground magnetic moment and exhibits a very hard magnetic hysteresis loop.