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An intraline of conical intersections for methylamine
1Department of Physics, Ben-Gurion University, Beer Sheva 84105, Israel.
The Journal of Chemical Physics
|July 8, 2008
Summary
Methylamine
Area of Science:
- Quantum chemistry
- Molecular spectroscopy
Background:
- Conical intersections (CIs) are crucial for understanding non-adiabatic dynamics in molecules.
- Previous studies on CIs often focused on isolated intersection points.
Purpose of the Study:
- To investigate conical intersections related to the N-H bond in methylamine (CH3NH2).
- To identify novel features of CIs in methylamine and their implications for molecular dynamics.
Main Methods:
- Theoretical analysis of non-adiabatic coupling terms (NACTs).
- Calculation of adiabatic potential energy surfaces (PESs).
- Berry phase calculation for a contour surrounding the CI line.
Main Results:
- A novel line of conical intersections (CIs) was discovered in the HC-NHH plane of methylamine.
- This line connects the two lowest adiabatic electronic states (1A' and 1A").
- The Berry phase associated with this line was calculated to be approximately pi (3.127 rad).
Conclusions:
- The identified line of CIs in methylamine differs from isolated CIs found in other molecules.
- The existence of this CI line may enhance inter-state transition rates.
- This finding offers numerical advantages for wave-packet treatments of nuclear dynamics.
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