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State specific stabilization of H+ + H2(j) collision complexes.
1Faculty of Mathematics and Physics, Charles University , 121 16 Prague, Czech Republic.
The Journal of Physical Chemistry. A
|March 19, 2013
Summary
This study investigated H3(+) collision complex stabilization at low temperatures. Unexpected results challenge standard models, suggesting low-energy dynamics influence reaction pathways.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Astrochemistry
Background:
- H3(+) is a key ion in interstellar chemistry.
- Understanding its stabilization is crucial for modeling chemical processes.
Purpose of the Study:
- Investigate the stabilization of H3(+) collision complexes.
- Measure state-specific rate coefficients for radiative and ternary stabilization.
- Compare experimental results with standard association models.
Main Methods:
- Utilized a 22-pole radio frequency (rf) ion trap.
- Studied para- and normal-hydrogen at temperatures from 11 to 33 K.
- Measured apparent binary rate coefficients at various hydrogen densities.
Main Results:
- Radiative stabilization rate coefficients (kr) were below 2 × 10(-16) cm(3) s(-1) and decreased with temperature.
- Ternary rate coefficients (k3) for para-hydrogen increased with temperature.
- Observed significant differences in state-specific ternary rate coefficients, contradicting standard models.
Conclusions:
- Experimental findings challenge conventional association models.
- Low-energy collision dynamics, involving limited partial waves, likely explain the unexpected results.
- Further quantum mechanical calculations are needed for radiative stabilization; three-body stabilization is more complex.
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