15min:

C. FOCSA, C. DUFOUR, B. PINCHEMEL, Laboratoire de Dynamique Moleculaire et Photonique, Centre d'Etudes et de Recherches Lasers et Applications, Universite de Lille, 59 655 Villeneuve d'Ascq cedex, France; I. HADJ BACHIR AND T. R. HUET, Laboratoire de Spectroscopie Hertzienne, Centre d'Etudes et de Recherches Lasers et Applications, Universite de Lille, 59 655 Villeneuve d'Ascq cedex, France..

A single mode cw dye laser along with velocity modulation detection was used to record the absorption spectrum of the the visible system of TiCl⁺ produced in an ac glow discharge between 17 100 and 18 600 cm^-1 with a gas mixture of He/TiCl₄. The translational temperature can be estimated to be about 800 K inducing narrow line shape. The rotational structure of the (0,0) and (1,0) vibrational bands has been observed and fully analysed for the main isotopomer Ti³⁵Cl⁺ as well as the (0,0) and (1,0) bands for Ti³⁷ Cl⁺. A set of molecular parameters has been obtained which includes the spin-orbit parameters thanks to the observation of the forbidden ³₂ - ³₂ and ³₃ - ³₃ intercombination transitions\footnote C. Focsa, C. Dufour, B. Pinchemel, I. Hadj Bachir, and T.R. Huet J. Chem. Phys. (submitted for publication). The X³(3d²) state was found to be perturbed. Additional spectra have been recorded with a better sensitivity in the same spectral range. In this communication we will report the observation of new bands. Among them, hot bands have already been identified, involving the v'' = 1 levels. The detailed analysis of the spectrum in this range is currently performed in order to determine a set of unperturbed molecular parameters for the ground state. Efforts are also in progress for producing other Ti - containing ions by introduction of a reactive gas into the discharge, in relation with the astrophysical interest of Ti containing compounds.