Infrared absorption spectroscopy of the 14N2+ Meinel system 2-1 band

PHYS 285

Bogdan Negru, negru@uiuc.edu1, Michael Wiczer1, Susanna L. Widicus Weaver, slww@uiuc.edu2, Joshua P. DiGangi3, Brian A. Tom1, and Benjamin J. McCall, bjmccall@uiuc.edu2. (1) Department of Physical Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Roger Adams Lab room 164, Urbana, IL 61801, (2) Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, (3) Department of Chemistry, University of Wisconsin - Madison, 1101 University Avenue, Madison, WI 53706-1322

The A2u-X2g+ system of N2+ was first observed in auroral emissions by Meinel in 1950.  Although the N2+ band system has been reinvestigated since this first spectral study, no laboratory spectrum of the 2-1 vibronic band has been obtained.  We have recently built a continuous-wave cavity ringdown spectrometer, and as a first test of this spectrometer we observed the 2-1 band of N2+ in a positive column discharge cell.  In the process of assigning this spectrum many lines of the first positive band system of N2* were also identified.  The relative intensities of the N2* and N 2+ bands were found to change with discharge cell pressure, and so each spectral region was observed at two pressures to aid in distinguishing the spectra of the two species.  We improved previous predictions of the molecular constants by obtaining a fit for both of these species and will present these results.

 

General Posters
7:30 PM-10:00 PM, Wednesday, March 28, 2007 Hyatt Regency Chicago -- Riverside Center, Poster

Division of Physical Chemistry

The 233rd ACS National Meeting, Chicago, IL, March 25-29, 2007