Rotational excitation in the electron impact ionization of supercooled N/sub 2/

Journal Article · Fri May 15 04:00:00 EDT 1981 · J. Chem. Phys.; (United States)

OSTI ID:6534822

DeKoven, B M; Levy, D H; Harris, H H; Zegarski, B R; Miller, T A

Electrons of controlled energy have been used to ionize and electronically excite N/sub 2/ cooled to a translational temperature of <2 /sup 0/K in a supersonic expansion either of pure N/sub 2/ or 10% N/sub 2//Ar. This source likely provides N/sub 2/ molecules ''frozen out'' in their N'' = 0 and 1 rotational levels. The rotational state distribution of B /sup 2/S/sup +//sub u/N/sup +//sub 2/ was determined by monitoring the rotationally resolved emission spectrum. Observation showed that even at high (approx.500 eV) impact energies, the N/sup +//sub 2/ rotational distributions are inconsistent with selection rules (DN = +- 1) for dipole excitation from N'' = 0 and 1. For lower electron impact energies the angular momentum content of the excited N/sup +//sub 2/ ion increases sharply. These observations are rationalized by a model which invokes interactions between the ion and the ejected electron.

• Research Organization: The James Franck Institute and the Department of Chemistry, The University of Chicago, Chicago, Illinois 60637
• OSTI ID: 6534822
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 74:10; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular &amp; Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
COLLISIONS
ELECTRON COLLISIONS
ELECTRON-MOLECULE COLLISIONS
ELEMENTS
EMISSION SPECTRA
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXCITED STATES
IONIZATION
MOLECULE COLLISIONS
NITROGEN
NONMETALS
ROTATIONAL STATES
SPECTRA