DISPERSED FLUORESCENCE SPECTROSCOPY OF THE $\tilde{B}$ $^2E'$ -- $\tilde{X}$ $^2A_2'$ TRANSITION OF NO$_3$

Abstract

We have generated NO$_3$ in supersonic free jet expansions and observed laser induced fluorescence (~LIF~) of the $\tilde{B}$ $^2E'$ -- $\tilde{X}$ $^2A_2'$ transition. We have measured LIF excitation spectrum and dispersed fluorescence (~DF~) spectra from the single vibronic levels (~SVL~) of the $\tilde{B}$ $^2E'$ state. Comparing with the vibrational structures of the DF spectra, vibrational structure of the $\tilde{X}$ $^2A_2'$ state has been analyzed. It is especially concluded that the 1,492 cm$^{-1}$ level in the $\tilde{X}$ $^2A_2'$ state has no contribution of the $\nu_4$ (~$e'$~) mode, though there are two opinions in which the level is attributed to the $\nu_3$ (~$e'$~) fundamental or the $\nu_3+\nu_4$ combination level.