The D–X system of the CuI molecule

Abstract

The fine structure of the D–X system of the CuI molecule has been reinvestigated following a doubtful and incomplete analysis of this system by Nair and Upadhya. The rotational structure was photographed in emission in the second order of a 10.6 m grating spectrograph with 0.33 Å/mm dispersion. Though the transition of the system was found to be the same as suggested by Nair and Upadhya, the molecular constants are considerably modified. The various molecular constants (cm−1) determined for the D1π state by using a weighted least-squares-fit computer program are as follows: Bc, 0.067 040(4); αc, 0.000 420(4); Dc, 0.250 × 10−7(3); q, −0.000 272(1); rc, 2.445 02(6) Å (1 Å = 10−10 m). The potential energy curve for the D1π state and Franck–Condon factors and r-centroids for the D–X system have also been reported.