15min:

MOURAD. ROUDJANE, TERRANCE J. CODD AND TERRY A. MILLER, Laser Spectroscopy Facility, The Ohio State University, Columbus, Ohio 43210.

The NO₃ radical is expected to exhibit a Jahn-Teller effect in its degenerate A²E'' electronic state. A more comprehensive understanding of its structure can be achieved using high resolution rotationally resolved absorption spectroscopy of its different vibronic bands. The high resolution absorption spectra of 4³₀ vibronic band of the A ²E'' excited state of NO₃ have been successfully recorded for the first time using our jet cooled cavity ring down apparatus. The parallel 4³₀ band is a vibronically allowed transition and shows the same contour as the one observed previously for 4ⁿ₀ (n=1,2).\footnote[2]Chen, M.W. et al. 66 ^th OSU International Symposium on Molecular Spectroscopy, The Ohio State University, Columbus, Ohio, 2011, talk WJ-04. The oblate symmetric top model Hamiltonian including both centrifugal distortion and spin rotation terms is used to analyze the spectrum. The rotational analysis of this band, supported by combination differences, demonstrate the existence of doubled lines as were observed for 4ⁿ₀ (n=1,2) bands.The possible sources of this splitting are being investigated.