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Potential energy surfaces and Jahn-Teller effect on CH4...NO complexes
Rachel Crespo-Otero1, Reynier Suardiaz, Luis Alberto Montero
1Laboratorio de Química Computacional y Teórica, Facultad de Química, Universidad de la Habana, 10400 Havana, Cuba.
The Journal of Chemical Physics
|September 18, 2007
Summary
This study explores the potential energy surface of CH4...NO van der Waals complexes, revealing dynamic Jahn-Teller systems. Calculated energies align well with experimental data for these molecular interactions.
Area of Science:
- Chemical Physics
- Computational Chemistry
- Spectroscopy
Background:
- Van der Waals complexes are crucial for understanding intermolecular forces.
- Jahn-Teller distortions significantly impact molecular stability and reactivity.
Purpose of the Study:
- To investigate the potential energy surface of CH4...NO van der Waals complexes.
- To analyze Jahn-Teller distortions and their effect on adiabatic surfaces.
- To compare theoretical calculations with experimental data.
Main Methods:
- High-level ab initio calculations using RCCSD(T)/aug-cc-pVTZ.
- Full counterpoise correction for basis set superposition error.
- Analysis of potential energy surfaces and Jahn-Teller distortions.
Main Results:
- Identified two adiabatic surfaces (A' and A") arising from Jahn-Teller distortion.
- Determined that CH3 face complexes exhibit dynamic Jahn-Teller behavior.
- Calculated dissociation energies (D0) of 140 cm⁻¹ (A") and 100 cm⁻¹ (A') for the complexes.
Conclusions:
- The theoretical findings support the dynamic Jahn-Teller nature of CH4...NO complexes.
- Calculated D0 values show excellent agreement with recent experimental measurements (103±2 cm⁻¹).
- This work provides valuable insights into the electronic structure and dynamics of these weakly bound systems.
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