Steric hindrances create a discrete linear Dy4 complex exhibiting SMM behaviour

Area of Science:

• Coordination Chemistry
• Materials Science
• Magnetochemistry

Background:

• Lanthanide complexes are investigated for their unique magnetic properties.
• Schiff-base ligands offer versatile coordination environments for metal ions.
• Single-molecule magnets (SMMs) are crucial for developing high-density data storage and quantum computing.

Purpose of the Study:

• To synthesize and characterize novel linear tetranuclear lanthanide complexes.
• To investigate the structural and magnetic properties of these complexes.
• To explore the potential of these complexes as single-molecule magnets (SMMs).

Main Methods:

• Synthesis of lanthanide complexes using a Schiff-base ligand (HL) and benzoate.
• X-ray crystallography for detailed structural analysis.
• Alternating current (ac) susceptibility measurements to probe magnetic behavior.

Main Results:

• Two discrete tetranuclear lanthanide complexes, [Ln(4)(L)(2)(C(6)H(5)COO)(12)(MeOH)(4)], were successfully synthesized with Dy(III) and Gd(III).
• Crystal structure revealed steric hindrance from Schiff-base ligands preventing 1D chain formation, isolating tetranuclear units.
• Complex 1 (Dy(III)) demonstrated frequency- and temperature-dependent out-of-phase signals in ac susceptibility, indicative of SMM behavior with an effective energy barrier of 17.2 K.

Conclusions:

• The steric bulk of the Schiff-base ligand is key to isolating discrete tetranuclear lanthanide complexes.
• The dysprosium(III) complex exhibits promising single-molecule magnet properties.
• These findings contribute to the design of novel lanthanide-based magnetic materials.