Evidence of the Existence of an He+3 Ion
Abstract
An ion-mobility apparatus was used to study the chemistry of helium ions in helium at gas pressures of 1-30 torr and temperatures of 300°-76°K. At temperatures below 200°K, the He2+ ion was observed to convert to an ion believed to be He3+. Identification of the He3+ was based upon observations of its behavior under varied experimental conditions. At 76°K, the rate of formation of He3+ from He2+ was faster than the three-body formation of He2+ from He+. The rate coefficient of the latter reaction was found to be 1.7 ± 0.4 × 10- 31 cm6/sec at 76°K. Between the temperatures of 135° and 200°K, He2+ and He3+ were present in equilibrium. A He3+ dissociation energy of 0.17 ± 0.03 was determined from measurements of the equilibrium constant as a function of temperature.
- Publication:
-
Journal of Chemical Physics
- Pub Date:
- April 1968
- DOI:
- 10.1063/1.1669660
- Bibcode:
- 1968JChPh..48.3625P