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Magnetic trapping of SH radicals
J S Eardley1, N Warner, L Z Deng
1Department of Chemistry, Joint Quantum Centre Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, UK. eckart.wrede@durham.ac.uk.
Physical Chemistry Chemical Physics : PCCP
|March 14, 2017
Summary
Researchers successfully magnetically trapped sulfur hydride (SH) radicals using the photostop technique. This method efficiently accumulates ground-state molecules for various trapping applications.
Area of Science:
- Chemical Physics
- Molecular Spectroscopy
- Quantum Control
Background:
- Sulfur hydride (SH) radicals are key intermediates in chemical reactions.
- Efficiently trapping and studying these radicals is crucial for understanding reaction dynamics.
Purpose of the Study:
- To demonstrate magnetic trapping of SH radicals produced via the photostop technique.
- To investigate the accumulation and lifetime of SH radicals in a static magnetic trap.
Main Methods:
- Producing SH radicals by photodissociating H2S at 212.8 nm within a 330 mK magnetic trap.
- Controlling molecular beam velocity to match SH photofragment recoil velocity for near-zero velocity production.
- Utilizing (2 + 1) REMPI for density measurements over seven orders of magnitude.
Main Results:
- SH radicals were successfully trapped in a static magnetic field.
- The 1/e trap lifetime of SH radicals was measured to be 40 ± 10 ms at a density of 5 × 10^4 molecules/cm³.
- Radicals exceeding 13 m/s escaped the trap within 5 ms.
Conclusions:
- The photostop technique provides a direct and simple method for accumulating ground-state SH radicals.
- Magnetic trapping of SH radicals is feasible and allows for extended study periods.
- This technique has potential for accumulating various ground-state molecules in traps.
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