Continuous-wave cavity ringdown spectroscopy of molecular ions in a fast ion beam

PHYS 266

Susanna L. Widicus Weaver, slww@uiuc.edu1, Andrew A. Mills2, and Benjamin J. McCall, bjmccall@uiuc.edu1. (1) Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, (2) Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801
A continuous-wave cavity ringdown spectrometer is being developed for high resolution mid-infrared spectroscopic studies of molecular ions in a fast ion beam. Discharge sources such as cold cathode or supersonic expansion sources can be used to produce the ion beam. Ion optics focus, collimate, and steer the ion beam into a drift region, separating the ions from the neutrals and greatly reducing the spectral complexity. These ions are then investigated with rotationally resolved continuous-wave cavity ringdown spectroscopy. This highly resolved, highly sensitive technique is a very powerful spectroscopic tool. The ion optics have been characterized and the ringdown system tested with N2+ produced from an uncooled cold cathode dc discharge source. Experiments involving a supersonic source to produce rotationally cold ions will soon be underway, and studies of CH5+ and CH3OH2+ are planned. We will report on the progress of the spectrometer development and the N2+, CH5+, and CH3OH2+ experiments.
 

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