Reinvestigation of the $\mathsf{B^{2}\Sigma^{ + }\rightarrow X^{2}\Sigma^{ + }}$ system in the CO$\mathsf{^ + }$ molecule

Abstract

Conventional, high resolution molecular spectroscopy has been employed to record emission spectra of the first negative bands system in the 12C16O+ molecule. Twenty two bands form the 0-v”,1-v”, 2-v”, 3-v”, 4-v”, 5-v” progressions and 6-10 band were photographed in the 34000-46000 cm-1 spectral region. The reduction of the spectrum for the individual bands has been performed via a nonlinear least-squares fit with the effective Hamiltonians of Brown et al. [J. Mol. Spectrosc. 74, 294 (1979)]. The final molecular constants for both the \(B^{2}\Sigma^{ + }(v=0 - 6)\) and \(X^{2}\Sigma^{ + }(v=0 - 10)\) states were obtained from global merge calculations of the present data of the \(B\rightarrow X\) system and previously obtained in our laboratory data for \(A \rightarrow X\) and \(B \rightarrow A\) systems in the CO + molecule. Merged molecular parameters have been used in order to the determine the equilibrium constants for both considered states. The \(\gamma_{e} = 2.194(14) \times 10^{-2}\) cm-1 and \(\alpha_{\gamma e} = -1.021(64)\times 10^{-4}\) cm-1 constants for the \(B^{2}\Sigma^{ + }\) state were obtained for the first time. The RKR potentials have been calculated for both combining states, as well as Franck-Condon factor and r-centroids for the first negative system in the 12C16O + molecule. Furthermore, we report the value of the electronic isotopic shift \(\Delta\nu_{e} = -0.395\) cm -1 of the \(B\rightarrow X\) system in 13C16O + , calculated on the basis the presents results and those obtained by us previously for the 13C16O + molecule.