Trends in Methanol-Solvated Actinide Ions and Actinide Expanded Porphyrin Complexes

Area of Science:

• Inorganic Chemistry
• Computational Chemistry
• Materials Science

Background:

• Trivalent actinide expanded porphyrin complexes are of synthetic interest.
• Previous research focused on lanthanide texaphyrin complexes.
• Synthesis of actinide-based complexes remains a challenge.

Purpose of the Study:

• To computationally investigate trivalent actinide ion interactions with expanded porphyrin macrocycles.
• To explore methanol as a solvent for stabilizing actinide complexes.
• To identify stable structures and understand bonding trends across the actinide series.

Main Methods:

• Relativistic density functional theory (DFT) calculations.
• Analysis of structural parameters and electronic structure.
• Evaluation of microsolvation stability and relative binding energies.

Main Results:

• Actinide contraction trends observed for early and mid actinides.
• Texaphyrin complexes adopt a planar structure, while alaskaphyrin complexes favor a bent structure.
• Bent structures in alaskaphyrin lead to stronger interaction energies.
• Redox-active ligands facilitate actinide accommodation via charge transfer.
• Both texaphyrin and alaskaphyrin show a strong binding preference for thorium.

Conclusions:

• Computational methods provide insights into actinide-ligand interactions.
• Expanded porphyrins can stabilize trivalent actinides through charge transfer.
• Thorium exhibits a strong affinity for both texaphyrin and alaskaphyrin ligands.