Prototype for In Situ Detection of Atmospheric NO3 and N2O5 via Laser-Induced Fluorescence

Wood, E.C., P.J. Wooldridge, J.H. Freese, T. Albrecht, and R.C. Cohen (2003), Prototype for In Situ Detection of Atmospheric NO3 and N2O5 via Laser-Induced Fluorescence, Environ. Sci. Technol., 37, 5732-5738, doi:10.1021/es034507w.
Abstract

We describe a prototype designed for in situ detection of the nitrate radical (NO3) by laser-induced fluorescence (LIF) and of N2O5 by thermal dissociation followed by LIF detection of NO3. An inexpensive 36 mW continuous wave multi-mode diode laser at 662 nm is used to excite NO3 iñ the B 2E ′(0000) r X 2A2(0000) band. Fluorescence is collected from 700 to 750 nm. The prototype has a sensitivity to NO3 of 76 ppt for a 60 s integration with an accuracy of 8%. Although this sensitivity is adequate for studies of N2O5 in many environments, it is much less sensitive (about 300 times) than expected based on a comparison of previously measured photophysical properties of NO2 and NO3. This implies much stronger nonradiative coupling of electronic states in NO3 than in NO2.

PDF of Publication
Download from publisher's website

 

Disclaimer: This material is being kept online for historical purposes. Though accurate at the time of publication, it is no longer being updated. The page may contain broken links or outdated information, and parts may not function in current web browsers. Visit https://espo.nasa.gov for information about our current projects.