Isotope effect of NO progressions in the region 800–850 Å

Abstract

The Rydberg absorption bands in the region below 1000 Å are investigated by means of the isotope shifts in the N 14O 16 spectra with the 3 and 6 m vacuum spectrographs. The bands at 829.38, 820.73, 812.73, and 804.80 Å fit well to the curve of the isotope shifts and form progression consisting of the (1,0), (2,0), (3,0), and (4,0) bands. The vibrational constant of the upper state in this progression, ω′ e = 1280 cm −1 (0.159 eV), is obtained from the isotope shifts. The rotational structure of the (3,0) band is resolved well by the high resolution spectrograph in this work. The isotope shifts of the previously assigned progressions are also examined in this work. Generally, the previous vibrational assignments of these progressions are doubtful. Tanaka's progression 2 and Huber's progession III are discussed as examples.