Peptoid-ligated pentadecanuclear yttrium and dysprosium hydroxy clusters.

Area of Science:

• Coordination Chemistry
• Materials Science
• Nanotechnology

Background:

• Coordination clusters offer tunable properties by incorporating various ligands.
• Cell-penetrating peptoids (CPPo) can enhance the cellular uptake of molecular constructs.
• Dibenzoylmethane (DBM) is a common ligand in coordination chemistry.

Purpose of the Study:

• To synthesize and characterize novel pentadecanuclear coordination clusters.
• To investigate the structural integrity and stability of these clusters in solution.
• To explore the magnetic properties, including single-molecule magnet (SMM) behavior and magnetic coupling.

Main Methods:

• Single-crystal X-ray crystallography for structural determination.
• Electrospray Ionization Mass Spectrometry (ESI-MS) to assess solution stability.
• Pulsed Gradient Spin Echo (PGSE) NMR diffusion measurements for structural confirmation.
• Static (dc) and dynamic (ac) magnetic property measurements.

Main Results:

• A new family of pentadecanuclear clusters, [{Ln15 (OH)20 (PepCO2 )10 (DBM)10 Cl}Cl4 ], with Ln=Y and Dy was synthesized.
• The cluster core {Ln15 (μ3 -OH)20 Cl}(24+) features a unique pentagonal cyclic structure.
• Clusters demonstrated robustness in solution and stability in their dicationic form.
• The dysprosium cluster exhibited slow relaxation of magnetization below 8 K, indicating SMM behavior.
• Ferromagnetic coupling was observed in the dysprosium cluster below 11 K.

Conclusions:

• The successful integration of inorganic cluster cores with organic cell-penetrating peptoids yields robust coordination compounds.
• These novel clusters display promising single-molecule magnet properties and ferromagnetic coupling.
• The findings open avenues for developing new magnetic materials with potential applications in nanotechnology.