Four-Centre, Multielectron Bonding in Rare-Earth Germole Sandwich Complexes

Area of Science:

• Organometallic Chemistry
• Materials Science
• Inorganic Chemistry

Background:

• Germole-ligated sandwich complexes offer a platform for exploring unusual bonding and electronic structures.
• Understanding the impact of reduction on metal-metal and metal-ligand interactions is crucial for designing new functional materials.

Purpose of the Study:

• To investigate the structural and electronic consequences of reducing germole-ligated sandwich complexes.
• To explore the reactivity and magnetic properties of the reduced species.

Main Methods:

• Synthesis and characterization of reduced sandwich complexes using KC8/2.2.2-cryptand.
• X-ray crystallography to determine structural changes.
• Computational analysis to understand bonding.
• EPR spectroscopy and magnetic measurements to probe electronic and magnetic properties.

Main Results:

• Successful synthesis of mono- and di-reduced complexes with contracted {M2Ge2} rings.
• Identification of four-center, multielectron {M2Ge2} bonds with tunable bond orders.
• Observation of spin delocalization in yttrium complexes.
• Significant exchange coupling in gadolinium complexes and single-molecule magnet behavior in dysprosium complexes.
• Demonstration of masked divalent reactivity in yttrium complexes.

Conclusions:

• Reduction of germole-ligated sandwich complexes leads to the formation of novel multielectron {M2Ge2} bonds.
• These complexes exhibit diverse electronic and magnetic properties, including single-molecule magnetism.
• The reduced yttrium complexes display masked divalent reactivity, opening avenues for further synthetic transformations.