Three intersecting {V₁₂} rings: {V₃₀Sb₈}, an ultra-large polyoxovanadate cluster shell.

Area of Science:

• Inorganic Chemistry
• Materials Science
• Solid-State Chemistry

Background:

• Polyoxovanadates (POVs) are versatile inorganic clusters with diverse structures and properties.
• Antimonato-polyoxovanadates (Sb-POVs) represent a subclass with unique structural and electronic characteristics.
• Exploring larger and more complex Sb-POVs is crucial for discovering novel chemical motifs and functionalities.

Purpose of the Study:

• To synthesize and characterize the largest known antimonato-polyoxovanadate, [V30SbIII8O78]12-.
• To investigate the unprecedented structural features, including concave motifs and trigonal pyramidal SbO3 units.
• To analyze the magnetic properties and spin topology of this complex cluster.

Main Methods:

• Single-crystal X-ray diffraction for structural determination.
• Infrared spectroscopy and elemental analysis for characterization.
• Magnetic susceptibility measurements for probing magnetic interactions.

Main Results:

• The synthesis of [V30SbIII8O78]12-, the largest known Sb-POV, was achieved.
• Unprecedented structural features were identified: three intersecting 12-membered rings forming a concave cavity and discrete trigonal pyramidal SbO3 units.
• The cluster exhibits a complex spin topology with 30 spin-1/2 sites and numerous geometrically frustrated motifs, leading to antiferromagnetic coupling.

Conclusions:

• The discovery of [V30SbIII8O78]12- expands the structural diversity of polyoxovanadates.
• The novel structural motifs offer new avenues for designing functional inorganic materials.
• The complex magnetic behavior highlights the potential for exploring frustrated magnetism in polyoxovanadate systems.