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Ne2+[II (1/2)u]: radiative decay and electronic predissociation
Sara Matt-Leubner1, Juraj Fedor, Rajendra Parajuli
1Institut für Ionenphysik, Leopold Franzens Universität, Technikerstr. 25, A-6020 Innsbruck, Austria. sara.matt@uibk.ac.at
Physical Chemistry Chemical Physics : PCCP
|October 2, 2009
Summary
Investigating metastable neon dimer ions revealed two distinct fragmentation pathways. These pathways, identified through kinetic energy release distributions, result from competing radiative and non-radiative decay processes in the excited ion.
Area of Science:
- Atomic and Molecular Physics
- Chemical Physics
- Spectroscopy
Background:
- Metastable states in molecular ions are crucial for understanding chemical dynamics.
- Neon dimer ions (Ne2+) present a unique system for studying fundamental ion-molecule interactions.
- Previous studies lacked the resolution to differentiate competing decay mechanisms in Ne2+.
Purpose of the Study:
- To investigate the metastable fragmentation of neon dimer ions.
- To resolve distinct kinetic energy release distributions arising from different reaction mechanisms.
- To elucidate the electronic transitions responsible for Ne2+ fragmentation.
Main Methods:
- High-resolution kinetic energy release distribution measurements.
- Modified mass-analyzed ion kinetic energy (MIKE) scan technique.
- Ab initio calculations of potential energy curves for Ne2+.
Main Results:
- Distinguished two distinct reaction mechanisms in the microsecond timescale.
- Observed unusual bimodal kinetic energy release distributions for Ne+ ions.
- Assigned fragmentation pathways to specific electronic transitions in excited Ne2+.
Conclusions:
- Metastable fragmentation of Ne2+ is governed by competing radiative and non-radiative decay.
- The long-lived Ne2+ II(1/2)u state plays a critical role in the observed fragmentation patterns.
- High-resolution techniques are essential for unraveling complex ion decay dynamics.
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