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Rotational spectrum and inversion motions in the neon-dimethyl sulfide complex
Sean A Peebles1, Rebecca A Peebles, Yoshio Tatamitani
1Department of Chemistry, Eastern Illinois University, Charleston, 61920, USA. sapeebles@eiu.edu
The Journal of Physical Chemistry. A
|June 2, 2006
Summary
The Ne-dimethyl sulfide (DMS) dimer
Area of Science:
- Physical Chemistry
- Molecular Spectroscopy
- Quantum Chemistry
Background:
- Dimethyl sulfide (DMS) is a molecule of interest in atmospheric and chemical studies.
- Rare gas dimers provide insights into weak intermolecular forces.
Purpose of the Study:
- To investigate the structure and dynamics of the Ne-DMS rare gas dimer.
- To characterize the intermolecular interaction between Neon (Ne) and Dimethyl Sulfide (DMS).
Main Methods:
- Fourier transform microwave spectroscopy was used to measure rotational spectra.
- Ab initio calculations (MP2/6-311++G(2d,2p)) were performed to model the potential energy surface.
- Dipole moment measurements were conducted.
Main Results:
- The Ne-DMS dimer exhibits C(s) symmetry with the Ne atom positioned above the DMS heavy atom plane.
- Experimental data indicate a S-Ne distance of 3.943(6) Å and a S-Ne angle of 63.2(6)°.
- Inversion splittings suggest a low barrier (20-40 cm⁻¹) for Ne atom tunneling across the DMS molecule.
Conclusions:
- The study elucidates the structural and dynamic properties of the Ne-DMS complex.
- Experimental and theoretical results are in good agreement, validating the proposed structure and dynamics.
- The findings contribute to understanding van der Waals interactions involving noble gases and organic molecules.
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