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Donor acceptor complexes of noble gases
Leonie Anna Mück1, Alexey Y Timoshkin, Moritz von Hopffgarten
1Philipps-Universität Marburg, Hans-Meerwein-Strasse, D-35032 Marburg, Germany.
Journal of the American Chemical Society
|February 27, 2009
Summary
Researchers developed novel "push-pull" cryptand ligands to create stable noble gas (Ng) complexes. These ligands overcome previous limitations, enabling the formation of the first thermodynamically stable argon (Ar) and krypton (Kr) compounds.
Area of Science:
- Inorganic Chemistry
- Computational Chemistry
- Materials Science
Background:
- Donor-acceptor (DA) complexes involving noble gases (Ng) were theoretically investigated.
- Previous studies faced challenges due to repulsive interactions and molecular reorganization energies, preventing stable complex formation.
Purpose of the Study:
- To theoretically explore the formation of stable noble gas complexes.
- To introduce a novel ligand design for overcoming limitations in noble gas complexation.
Main Methods:
- Ab initio and Density Functional Theory (DFT) methods were employed for theoretical studies.
- Analysis of bonding interactions, including electrostatic and orbital contributions, was performed.
- A novel cryptand-type ligand with separated donor and acceptor fragments was designed and evaluated.
Main Results:
- Model compounds like F(3)Al-Ng-NH(3) showed repulsive Ng-ammonia interactions but attractive Ng-AlF(3) interactions.
- Individual donor-acceptor molecules failed to form stable complexes, leading to dissociation.
- The proposed "push-pull" cryptand ligands are predicted to form stable complexes with noble gases exothermically.
- The first thermodynamically stable argon (Ar) and krypton (Kr) compounds were predicted.
Conclusions:
- Novel "push-pull" cryptand ligands enable the formation of stable noble gas complexes.
- This approach overcomes previous thermodynamic and kinetic barriers to noble gas complexation.
- The developed ligands offer potential for creating stable complexes with various electron-rich elements.
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