Translational energy release in dissociative electron attachment has been investigated at subthermal electron energies through study of electron transfer reactions of the type K($n$d) + RX $\to$ K$\sp +$ + RX$\sp{-\*} \to$ K$\sp +$ + X$\sp -$ + R. The translational energy release is measured using a novel time-of-flight technique developed in the present work that incorporates position sensitive detection of the product ions. Data for CCl$\sb4$ and CFCl$\sb3$ show that the energy released by electron capture is well-distributed among the internal modes of the intermediate negative ion prior to dissociation. In this case, the kinetic energy release distributions are in good agreement with the predictions of quasi-equilibrium theories of unimolecular decay. In contrast, data for CF$\sb3$I and CF$\sb3$Br point to electron capture directly into an antibonding orbital localized on the I or Br atom followed by immediate dissociation before significant redistribution of excess energy can occur. The present results raise questions about the reliability of certain techniques for measurement of low energy electron attachment rate constants.
| Identifer | oai:union.ndltd.org:RICE/oai:scholarship.rice.edu:1911/16307 |
| Date | January 1989 |
| Creators | Walter, C. Wesley |
| Contributors | Dunning, F. B. |
| Source Sets | Rice University |
| Language | English |
| Detected Language | English |
| Type | Thesis, Text |
| Format | 122 p., application/pdf |
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