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Published on: February 20, 2020
Ion-pair dissociation dynamics of Cl2: adiabatic state correlation
Chang Zhou1, Yusong Hao, Yuxiang Mo
1Department of Physics and Key Laboratory for Atomic and Molecular Nanosciences, Tsinghua University, Beijing, 100084, China.
The Journal of Physical Chemistry. A
|August 16, 2008
Summary
We studied Cl2 ion-pair dissociation using extreme ultraviolet (XUV) radiation and velocity map imaging. Results reveal insights into Rydberg state predissociation dynamics and spin-orbit component branching ratios.
Area of Science:
- Molecular Physics
- Quantum Chemistry
- Spectroscopy
Background:
- Understanding molecular dissociation dynamics is crucial for chemical reaction mechanisms.
- Ion-pair formation provides insights into electronic structure and bonding.
Purpose of the Study:
- Investigate the ion-pair dissociation dynamics of Cl2 using extreme ultraviolet (XUV) radiation.
- Determine branching ratios and anisotropic parameters for Cl(+) spin-orbit components.
- Elucidate the predissociation mechanism of Rydberg states.
Main Methods:
- Coherent extreme ultraviolet (XUV) radiation for excitation.
- Velocity map imaging (VMI) technique for fragment ion analysis.
- Spectroscopic analysis of ion-pair yield and fragment images.
Main Results:
- Measured the ion-pair yield spectrum of Cl2 in the 12.41-12.74 eV range.
- Determined branching ratios and anisotropic parameters (beta) for Cl(+)((3)P2, (3)P1, (3)P0) spin-orbit components.
- Identified parallel and perpendicular transitions corresponding to specific Rydberg series, [A(2)Pi(u)]3d pi(g), (1)Sigma(u)(+) and [A(2)Pi(u)]5s sigma(g), (1)Pi(u).
Conclusions:
- The ion-pair dissociation mechanism is driven by predissociation of Rydberg states converging to Cl2(+)(A(2)Pi(u)).
- Spin-orbit component production shows distinct preferences for parallel or perpendicular transitions.
- Conservation of the electronic angular momentum projection (Omega) is observed in most predissociation events.
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