VIBRONIC INTERACTIONS IN $CO_{2}^{+}$ AND THE PERTURBED. $\bar{B}$(000) STATE

1. D. Gauyacq, M. Horani, S. Leach, and J. Rostas, Can. J. Phys. 53, 2040-2059 (1975). $^{2}$. J. Rostas and R. P. Tuckett, J. Mol. Spectrosc. 96, 77-86 (1982). $^{3}$. M. A. Johnson, R. N. Zare, J. Rostas, and S. Leach, J. Chem. Phys. 80, 2407-2428 (1984).Author Institution: Laboratoire de Photophysique Moleculaire du CNRS, Batiment 213, Universite de Paris-Sud; Department of Chemistry, St. Francis Xavier, University; Herzberg Institute of Astrophysics, National Research Council of CanadaIt has been known for many $years^{1}$ that the (000) level of the $\bar{B}^{2}\Sigma^{+}_{u}$ state of the $Co_{2}^{+}$ ion is severely perturbed at low values of $J. Emission^{2}$ and laser excitation $spectra^{3}$ with low rotational temperatures have given low. J rotational term values for the e and f components of the $\bar{B}(000)$ state and of two perturbing states. The present work is concerned with rotational analyses of new emission spectra at rotational temperatures of about 40 K and 200 K from the perturbed $\bar{B}(000)$ state to high levels (up to $10000 cm^{-1})$ of the ground state. These bands, whose intensity is due to the perturbing states, are shown to be parallel bands to $^{2}\Sigma^{+}_{}g$ and $^{2}\Sigma^{-}_{}g$ vibronic levels with odd values of the vibrational quanturm numbers $\nu_{2}$ and $\nu_{3}$ in the ground $\bar{X}^{2}\Pi_{}$g electronic state. The states perturbing the $\bar{B}(000)$ state, which must therefore be one $^{2}\Sigma^{+}_{u}$ state and one $^{2}\Sigma^{-}_{}g$ state, are assigned to the vibronic levels $\bar{A}(231)\mu^{2}\Sigma^{+}_{u}$ and $\bar{A}(151)\kappa^{2}\Sigma^{-}_{u}$ of the $\bar{A}^{2}\Pi_{u}$ electronic state. Improved vibronic parameters for the $\bar{X}^{2}\Pi_{g}$ and $\bar{A}^{2}\Pi_{u}$ electronic states are obtained