Quantifying Actinide-Carbon Bond Covalency in a Uranyl-Aryl Complex Utilizing Solution ¹³C NMR Spectroscopy

Area of Science:

• Organometallic Chemistry
• Uranium Chemistry
• Coordination Chemistry

Background:

• Uranium's unique electronic structure presents challenges and opportunities in organometallic chemistry.
• Understanding the nature of bonding in uranyl complexes is crucial for various applications.

Purpose of the Study:

• To synthesize and characterize novel uranyl aryl complexes.
• To investigate the electronic structure and bonding characteristics of these complexes.

Main Methods:

• Synthesis of uranyl aryl complexes via reaction of [UO2Cl2(THF)2]2 with LiFmes.
• Characterization using X-ray crystallography and NMR spectroscopy.
• Density Functional Theory (DFT) calculations to probe electronic structure.

Main Results:

• Formation of uranyl aryl complexes [Li(THF)3][UO2(Fmes)3] and [Li(Et2O)3(THF)][UO2(Fmes)3].
• Structural elucidation through X-ray crystallography and NMR spectroscopy.
• DFT calculations indicated significant covalency in the U-C bond, attributed to spin-orbit coupling.

Conclusions:

• Successful synthesis of novel uranyl aryl complexes.
• Demonstrated appreciable covalency in U-C bonding through computational analysis.
• Highlights the influence of spin-orbit coupling on electronic properties of uranyl complexes.