Modern High Temperature Science pp 171-179 | Cite as
Observations of Excited Metastable and Radiative States of He2, Ne2, and Ar2 by Neutralized Ion-Beam Spectroscopy
Chapter
Abstract
Rare gas dimers formed when a fast beam of X 2 + (X = He, Ne, Ar) is neutralized in the reaction
have been studied by neutralized ion beam techniques. From measurements of the kinetic energy released in the dissociation of X 2 * and with consideration of available spectroscopic information, it is proposed that the neutral dimers are formed initially in their first excited singlet and triplet electronic states. Estimates of the radiative lifetimes of the 3∑ u + states of He 2 * , Ne 2 * , Ar 2 * are >3.2, >7.2, and 2.1 µs, respectively. Radiation from the 1∑ u + → X 1∑ g + transitions is predicted to occur at λ ≈ 83, 80, and 114 nm for He2, Ne2, and Ar2, respectively. Ion beam attenuation cross-sections for He 2 + , Ne 2 + , and Ar 2 + are 250, 180, and 80 Å2, respectively, indicating that electron transfer from K(g) is a highly efficient process. The capability of generating relatively intense beams of metastable He2 and Ne2 dimers may have applications for other beam experiments.
$$ X_2^ + + {K_{(g)}} \to X_2^* + {K^ + } $$
Index Entries
Ion beam spectroscopy, of He2, Ne2, and Ar2 spectroscopy, of He2, Ne2, and Ar2 by ion beams He2, ion beam spectroscopy of Ne2, ion beam spectroscopy of Ar2, ion beam spectroscopy of metastable excited states, of He2, Ne2, and Ar2 radiative states, of He2, Ne2, and Ar2Preview
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© The Humana Press Inc. 1984