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Breaking Symmetry Relaxes Structural and Magnetic Restraints, Suppressing QTM in Enantiopure Butterfly Fe₂ Dy₂ SMMs*.

ABSTRACT: The {Fe₂ Dy₂ } butterfly systems can show single molecule magnet (SMM) behaviour, the nature of which depends on details of the electronic structure, as previously demonstrated for the [Fe₂ Dy₂ (μ₃ -OH)₂ (Me-teaH)₂ (O₂ CPh)₆ ] compound, where the [N,N-bis-(2-hydroxyethyl)-amino]-2-propanol (Me-teaH₃ ) ligand is usually used in its racemic form. Here, we describe the consequences for the SMM properties by using enantiopure versions of this ligand and present the first homochiral 3d/4 f SMM, which could only be obtained for the S enantiomer of the ligand for [Fe₂ Dy₂ (μ₃ -OH)₂ (Me-teaH)₂ (O₂ CPh)₆ ] since the R enantiomer underwent significant racemisation. To investigate this further, we prepared the [Fe₂ Dy₂ (μ₃ -OH)₂ (Me-teaH)₂ (O₂ CPh)₄ (NO₃ )₂ ] version, which could be obtained as the RS-, R- and S-compounds. Remarkably, the enantiopure versions show enhanced slow relaxation of magnetisation. The use of the enantiomerically pure ligand suppresses QTM, leading to the conclusion that use of enantiopure ligands is a "gamechanger" by breaking the cluster symmetry and altering the intimate details of the coordination cluster's molecular structure.

SUBMITTER: Baniodeh A

PROVIDER: S-EPMC8596739 | biostudies-literature |

REPOSITORIES: biostudies-literature

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