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The gas-phase structure of dimethyl peroxide
Olfa Ferchichi1, Najoua Derbel, Nejm-Eddine Jaidane
1LSAMA, Laboratoire de Spectroscopie Atomique, Moléculaire et Applications, Département de Physique, Faculté des Sciences, Université Tunis - El Manar, 1060 Tunis, Tunisia. ferchich.olfa91@gmail.com najoua.derbel@gmail.com.
Physical Chemistry Chemical Physics : PCCP
|August 2, 2017
Summary
Dimethyl peroxide
Area of Science:
- Quantum Chemistry
- Molecular Spectroscopy
- Computational Chemistry
Background:
- The gas-phase structure of dimethyl peroxide has been a long-standing debate.
- Disagreements exist between experimentalists and theoreticians regarding its molecular configuration.
Purpose of the Study:
- To definitively resolve the gas-phase structure of dimethyl peroxide.
- To reconcile conflicting experimental and theoretical findings on its molecular geometry.
Main Methods:
- High-level coupled cluster calculations, specifically CCSD(T)-F12 and MRCI methods.
- Analysis of torsional motion using numerical wavefunctions and MP2/aug-cc-pVTZ potential energy curves.
Main Results:
- The COOC fragment adopts a trans-structure at the potential energy surface minimum.
- Slow torsional motion influences the molecule's dynamical structure.
- Computational and experimental results are in complete agreement.
Conclusions:
- The thirty-year-old debate on dimethyl peroxide's gas-phase structure is resolved.
- This study provides a unified understanding of its static and dynamic structures.
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