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The K2 2(3)Pi(g) state: new observations and analysis.
1Department of Physics and Key Laboratory of Atomic and Molecular Nanosciences, Tsinghua University, Beijing 100084, China.
The Journal of Physical Chemistry. A
|September 29, 2006
Summary
This study observed 3045 rovibrational transitions in the K2 2(3)Pi(g) state, revealing molecular constants and spin-orbit interactions. Perturbations were linked to spin-orbit coupling with the 4(1)Sigma(g)+ state.
Area of Science:
- Molecular Spectroscopy
- Quantum Chemistry
- Atomic and Molecular Physics
Background:
- The K2 2(3)Pi(g) state is crucial for understanding molecular interactions and electronic structures.
- Investigating rovibrational levels provides insights into potential energy surfaces and interatomic forces.
Purpose of the Study:
- To precisely determine molecular constants and spin-orbit interaction parameters for the K2 2(3)Pi(g) state.
- To elucidate the perturbations observed in the rovibrational levels and their underlying causes.
Main Methods:
- Infrared-infrared double resonance fluorescence excitation spectroscopy.
- Two-photon spectroscopy.
- Analysis of 3045 observed rovibrational transitions.
Main Results:
- Observed 3045 transitions across v = 0-42 and J = 0-103 for the 2(3)Pi(g) state.
- Determined molecular constants and spin-orbit interaction parameters, including A0 ≈ 14.17 cm(-1).
- Identified strong mixing with 3P ionic states, leading to a large equilibrium internuclear distance (Re = 5.254 Å).
Conclusions:
- The observed perturbations in the 2(3)Pi(g) state are primarily due to spin-orbit coupling with the 4(1)Sigma(g)+ state.
- The electronic mixing significantly influences the molecular constants and dissociation behavior.
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