Fluorescence of the γ, ε and Δ systems of nitric oxide; polarization and use of calculated intensities for spectrometer calibration

Abstract

Fluorescence of the γ system of nitric oxide was obtained by excitation from both the 2144 Å line of ionized cadmium and a continuum source. Individual rotational lines of the 2144 Å excited fluorescence spectrum were found to be partially polarized and to have polarizations of differing sign. Measured relative vibrational band intensities from line and continuum excitation were compared to calculated Franck-Condon factors. Those Franck-Condon factors based on a single potential for the two spin states of the X²Π state agreed better with measured values than those based on separate potentials for the two spin states. Calculated intensities of the v' = 3 progression were used to calibrate the instrument response in the wavelength region of 2000–2500 Å and were checked with measured intensities of the v' = 0, 1 and 2 progressions. Fluorescence of the ϵ and σ bands obtained with continuum lamp excitation also were compared to calculated intensities.