Ionization of xenon atoms in high Rydberg states by collision with molecules

Abstract

Ionization of xenon atoms in single highly excited states ‖nf≳ (where 25⩽n⩽40) by collisions with CCl4, CCl3F, and SF6 has been investigated. Absolute rate constants for Xe+ production are reported together with the identities of the major negatively charged species produced in the collisions. Cross sections determined from these rate constants are also given. The data lend support to the theoretical model, which views such collisions as being dominated by the interaction between the target molecules and the excited electron, with the Xe+ ion core playing a minor role.

Electron transfer from laser excited rydberg atoms to molecules. Absolute rate constants at low and intermediate principal quantum numbers

“…Strong evidence for this behaviour has been given by the n-dependence of the measured rate constants k,z for ion pair formation in A(nl)+SF 6 collisions, which was shown to be constant for high n in several experiments involving different Rydberg systems [4,7,11,17]. Some disagreement, however, exists with respect to the absolute value of k,l.…”

“…As is well known [7,11,13,27,40], electron transfer in the reaction A(nl)+ CC14 leads exclusively to C1-negative ions (dissociative electron transfer). We found, according to reaction (6), the same behaviour for the systems Ne(ns, nd)+CCl4 in the range 6~< n*~< 30 with cross sections as shown in Fig.…”

“…While electronic collisions lead to a Rydberg state population with a broad band of principal quantum number n and orbital quantum number t [1,5,10], the application of tunable lasers allows the selective excitation of a particular A(nl) level of various atoms [2,6], especially of the alkali metal atoms [2, 6, 13, i5-19]. In spite of the high ionization energies of the rare gases their Rydberg states are also easily accessible, if the laser excitation starts from the metastable levels [2,7,12,14,20].…”

“…(2) (7 e At large principal quantum numbers the study of process (1) hence yields information on the electron collision process at ultralow energies [2,4,7,11,21].…”

Electron ionization time‐of‐flight mass spectrometry: Historical review and current applications

“…For more details on collisions between Rydberg atoms and molecules, the reader is referred to the review articles by Matsuzawa (1983) and Fabrikant (1996). Since Fermi's original contribution, there has been a considerable body of theoretical (Matsuzawa, 1971(Matsuzawa, ,1972a(Matsuzawa, ,b, 1974 and experimental (Stockdale et al, 1974;West et al, 1976;Foltz et al, 1977) evidence to suggest that the rate constant for the transfer of a loosely bound Rydberg electron to an electronattaching molecule should be equal to the electron attachment rate for free electrons at the equivalent energy. Perhaps the best experimental evidence for this equivalence comes from the unpublished Rydberg electron-transfer reaction rate data of W. A.…”