Unprecedented hexagonal bipyramidal single-ion magnets based on metallacrowns

Area of Science:

• Coordination Chemistry
• Materials Science
• Magnetism

Background:

• Lanthanide complexes are investigated for their unique magnetic properties.
• Single-ion magnets (SIMs) offer potential for high-density data storage and quantum computing.
• Metallacrowns provide novel ligand scaffolds for coordinating lanthanide ions.

Purpose of the Study:

• To synthesize and characterize novel lanthanide complexes with a [15-MC-6] metallacrown ligand and phosphine oxide.
• To investigate the structural and magnetic properties of these new complexes.
• To determine the magnetic relaxation mechanisms in the lanthanide single-ion magnets.

Main Methods:

• Single-crystal X-ray diffraction for structural determination.
• Magnetic susceptibility measurements (DC and AC).
• Analysis of magnetic data to identify relaxation mechanisms.

Main Results:

• Two new lanthanide complexes, Ce(iii) and Nd(iii), were synthesized.
• The lanthanide ions exhibit a near-hexagonal bipyramidal DyO8 coordination geometry with pseudo-D6h symmetry.
• Both complexes function as single-ion magnets (SIMs), with slow magnetic relaxation primarily governed by the Raman process.

Conclusions:

• The [15-MC-6] metallacrown ligand effectively stabilizes lanthanide ions in a specific geometry conducive to SIM behavior.
• The observed Raman relaxation mechanism provides insights into the magnetic dynamics of these lanthanide SIMs.
• These findings contribute to the development of molecular magnetic materials.