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Doubly charged negative atomic ions of hydrogen
Science (New York, N.Y.)
|February 6, 1976
Summary
Researchers have demonstrated the existence of the doubly charged negative atomic ion H(2-), isoelectronic with lithium. This ion has a half-life of 2.3 x 10(-8) seconds before dissociating into H(-) ions.
Area of Science:
- Atomic and Molecular Physics
- Quantum Chemistry
- Plasma Physics
Background:
- Doubly charged negative atomic ions are rare and challenging to study.
- The H(2-) ion, isoelectronic with lithium, has been theorized but experimentally elusive.
- Understanding such species provides insights into fundamental atomic interactions.
Purpose of the Study:
- To experimentally demonstrate the existence of the H(2-) ion.
- To characterize the properties and lifetime of the H(2-) ion.
- To investigate the dissociation pathways of H(2-).
Main Methods:
- Formation of H(2-) in a hydrogen plasma.
- Mass spectrometry combined with ion energy, velocity, and momentum analysis.
- Detection of H(2-) and its dissociation products.
Main Results:
- Experimental evidence for the existence of the H(2-) ion.
- Measured half-life of H(2-) as 2.3 x 10(-8) seconds.
- Observed spontaneous dissociation of H(2-) into H(-) ions.
Conclusions:
- The existence of the H(2-) ion is experimentally confirmed.
- The H(2-) ion is a relatively long-lived species with a measurable half-life.
- The study provides crucial data for atomic physics and plasma chemistry.
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