Near infrared emission spectra of CoH and CoD

New high resolution emission spectra of CoH and CoD molecules have been recorded in the 640 run to 3.5 mu m region using a Fourier transform spectrometer. The bands were excited in a carbon tube furnace by the reaction of cobalt metal vapor and a mixture of H-2 or D-2 With He at a temperature of about 2600 degrees C. Eight bands were observed for the A(t3)Phi(4)-X-3 Phi(4) electronic transition of CoD, and five bands for the corresponding transition of CoH. The (0,0) bands of the A(t3)Phi(3)-X-3 Phi(3) system Were also recorded for both isotopologues, although one of the parity components in the X-3 Phi(3) sub-state of CoH was found to be perturbed. The A(t3)Phi(3)-X-3 Phi(4) transition was also observed in our spectrum of CoH. In addition, a new [13.3]4 electronic state was found by observing [13.3]4-X-3 Phi(3) and [13.3]4-X-3 Phi(4) transitions in the spectrum of CoD. Analysis of the transitions with Delta Omega = 0, +/- 1 provided more accurate values of spin-orbit splittings between Omega = 4 and Omega = 3 components. The around-state data for both molecules were fitted both to band-constant and Dunham-expansion expressions, and a combined-isotopologue analysis of the X-3 Phi(4) spin component was carried out using the data for CoH and CoD. The tipper states Were represented by term values in these analyses because of perturbations, but estimated band constants for them were obtained in separate fits in which ground-state constants were held fixed. (C) 2006 Elsevier Inc. All rights reserved.