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Stabilization of HHeF by complexation: is it a really viable strategy?
Maria Giordani1, Paola Antoniotti, Felice Grandinetti
1Dipartimento di Scienze Ambientali, Università della Tuscia, L.go dell' Università, s.n.c., 01100 Viterbo, Italy.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|April 17, 2010
Summary
This study explores fluorine-coordinated complexes of HHeF with various ligands, revealing significant structural changes and large complexation energies. These findings question the overall stabilization of HHeF through complexation.
Area of Science:
- Theoretical Chemistry
- Computational Quantum Chemistry
- Spectroscopy
Background:
- The HHeF molecule, a noble gas hydride, presents unique chemical properties.
- Understanding the stability and reactivity of HHeF complexes is crucial for advancing noble gas chemistry.
Purpose of the Study:
- To investigate the theoretical existence and properties of fluorine-coordinated complexes of HHeF.
- To analyze the structural, electronic, and energetic effects of complexation with various ligands.
Main Methods:
- Ab initio calculations using MP2 and CCSD(T) levels of theory.
- Analysis of structural parameters, vibrational frequencies, and complexation energies.
Main Results:
- Ligand complexation significantly alters H-He and He-F bond distances and vibrational frequencies.
- Exceptional blueshifts (750-1000 cm(-1)) in the H-He stretching mode were observed.
- Large complexation energies (20-60 kcal mol(-1)) were calculated, stabilizing complexes against dissociation.
- A strong inverse relationship between complexation energy and bending barrier was established.
Conclusions:
- HHeF-ligand complexes exhibit pronounced structural and electronic changes.
- Despite high stability against dissociation, complexation significantly lowers the bending barrier, impacting overall stability.
- Calculations cast doubt on the conceivable stabilization of HHeF through complexation with the studied ligands.
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