New analysis of the Comet-Tail (AΠi − XΣ) system in the CO isotopic molecule

The emission spectra of the 0-2, 4-2, and 6-1 bands of the Comet-Tail (A²Π_i − X²Σ⁺) system in the ¹⁴C¹⁶O⁺ isotopic molecule, comprising nearly 600 lines, have been recorded and analyzed for the first time. The spectra have been photographed under high resolution by using conventional spectroscopy, and it was possible to separate and observe most of the lines of all the 12 branches of this transition. The reduction of the individual bands’ spectra has been performed by nonlinear least-squares procedure and by means of effective Hamiltonians of Brown et al. the rovibronic structure parameters have been obtained. The currently investigated bands of the Comet-Tail system and the earlier analyzed bands of the A − X and B − A systems in the ¹⁴C¹⁶O⁺ molecule have been merged together. The results of this global fit made it possible to derive a new set of the equilibrium molecular constants for the A and X states. Then the RKR potential curve parameters for both A and X states and Franck-Condon factors as well as r-centroids for the A − X transition have been calculated for the ¹⁴C¹⁶O⁺ molecule.