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Slow Magnetic Relaxation in Mono- and Bimetallic Lanthanide Tetraimido-Sulfate S(NtBu)₄ ^2- Complexes.

ABSTRACT: Lanthanide ions are particularly well-suited for the design of single-molecule magnets owing to their large unquenched orbital angular momentum and strong spin-orbit coupling that gives rise to high magnetic anisotropy. Such nanoscopic bar magnets can potentially revolutionize high-density information storage and processing technologies, if blocking temperatures can be increased substantially. Exploring non-classical ligand scaffolds with the aim to boost the barriers to spin-relaxation are prerequisite. Here, the synthesis, crystallographic and magnetic characterization of a series of each isomorphous mono- and dinuclear lanthanide (Ln=Gd, Tb, Dy, Ho, Er) complexes comprising tetraimido sulfate ligands are presented. The dinuclear Dy complex [{(thf)₂ Li(NtBu)₂ S(tBuN)₂ DyCl₂ }₂ ⋅ ClLi(thf)₂ ] (1c) shows true signatures of single-molecule magnet behavior in the absence of a dc field. In addition, the mononuclear Dy and Tb complexes [{(thf)₂ Li(NtBu)₂ S(tBuN)₂ LnCl₂ (thf)₂ ] (2b,c) show slow magnetic relaxation under applied dc fields.

SUBMITTER: Jung J

PROVIDER: S-EPMC8453918 | biostudies-literature |

REPOSITORIES: biostudies-literature

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