ROTATIONAL AND HYPERFINE ANALYSIS OF THE A’(3)PHI(4)-X(3)PHI(4) TRANSITIONS OF COH AND COD

Three new bands of CoH and five new bands of CoD have been observed using laser excitation in the visible and near-infrared, following reaction of Co atoms with H-2 or D-2 under supersonic jet-cooled conditions. All the bands reported here, together with two reported previously by Varberg et al. (J. Mol. Spectrosc. 138, 630-637, 1989), are shown to belong to a single electronic transition with an origin near 12 400 cm(-1), here designated A’(3) Phi(4)-X(3) Phi(4). High-resolution spectra of the (0, 0) bands of both CoH and CoD reveal extensive hyperfine structure associated with the Co-59 nucleus, which shows that the electron configuration of the A’(3) Phi state is (7 sigma)(1)(3d delta)(3)(3d pi)(3)(8 sigma)(1). Wavelength-resolved fluorescence from one of the CoD bands has given the Omega = 4-3 spin-orbit interval for the X(3) Phi state as 729 cm(-1) and confirmed the presence of a low-lying Omega = 3 electronic state similar to 2444 cm(-1) above the ground state. (C) 1995 Academic Press, Inc.