Study of low energy electron-molecule and ion-molecule collisions using Rydberg atoms
Low energy collisions between Rydberg atoms and neutral molecules have been investigated over a wide range of principal quantum numbers n, and for several different neutral targets. The results have been used to validate the free-electron, independent particle model of Rydberg atom collisions. Comparison between theory and experiment show that at large values of n, ionization of Rb(nS,nD) Rydberg atoms in the reaction, Rb(nS,nD) + SF/sub 6/ ..-->.. Rb/sup +/ = SF/sub 6//sup -/ proceeds by electron transfer from the Rydberg atoms to the SF/sub 6/ molecule. The rate constants measured for this reaction are much the same as for the attachment of free, low-energy electron s to SF/sub 6/. Thus, Rydberg collision studies can provide information about low-energy free electron interactions. Studies of the rate constants for free ion production in the reaction, K(nD) + SF/sub 6/ ..cap alpha.. K/sup +/ + SF/sub 6//sup -/, showed these to decrease sharply at smaller n, falling far below the value expected on the bases of Rydberg electron attachment to SF/sub 6/. This behavior is attributed not to breakdown of the free-electron model, but to post-attachment electrostatic interactions between the productions, which are formed closer to each other at lower n. Model calculations that take this electrostatic interaction into account confirm this prediction.
- Research Organization:
- North Carolina Univ., Chapel Hill (USA)
- OSTI ID:
- 6931153
- Country of Publication:
- United States
- Language:
- English
Similar Records
Observation of l-dependent rate constants for ion production in Rydberg electron transfer reactions
Ionizing collisions of He( n sup 1 P ) atoms in a low-Rydberg state with SF sub 6 and NO sub 2 electron-attaching molecules
Related Subjects
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
COLLISIONS
ELECTRON COLLISIONS
ELECTRON TRANSFER
ELECTRON-MOLECULE COLLISIONS
ENERGY LEVELS
EXCITED STATES
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
ION COLLISIONS
ION-MOLECULE COLLISIONS
IONIZATION
MOLECULE COLLISIONS
RYDBERG STATES
SULFUR COMPOUNDS
SULFUR FLUORIDES