Slow magnetic relaxation in lanthanide ladder type coordination polymers

Area of Science:

• Coordination Chemistry
• Materials Science
• Magnetism

Background:

• Lanthanide coordination polymers are explored for unique magnetic properties.
• One-dimensional (1D) coordination polymers offer specific structural arrangements for magnetic interactions.

Purpose of the Study:

• Synthesize and characterize novel isostructural lanthanide coordination polymers.
• Investigate the magnetic behavior of these new materials.

Main Methods:

• Hydrothermal synthesis of lanthanide coordination polymers.
• Structural characterization using X-ray diffraction, elemental analysis, IR spectroscopy, and thermogravimetric analysis.
• Magnetic property evaluation via static magnetization and AC magnetic susceptibility measurements.

Main Results:

• Four isostructural 1D coordination polymers, Ln(glu)(pic)(H2O)2 (Ln = Gd, Tb, Dy, Er), were successfully synthesized.
• Compounds exhibit a ladder-type structure with double-bridged lanthanide ion pairs.
• Gd(III), Dy(III), and Er(III) compounds display frequency-dependent AC susceptibility and slow magnetization relaxation, classifying them as molecular magnets.

Conclusions:

• The synthesized lanthanide coordination polymers demonstrate potential as molecular magnets.
• Magnetic behavior is attributed to single-ion anisotropic effects and potentially phonon-bottleneck relaxation, rather than solely the ladder chain structure.