Theoretical and experimental studies of radiative lifetimes of excited electronic states in CO+

Analytical potential energy functions for CO + in its ground and excited electronic states

CONTEXT

Accurate functions to analytically represent the potential energy interactions of CO+ diatomic system inX 2 Σ + ,A 2 Π , andB 2 Σ + electronic states are proposed. The new functions depend upon only four parameters directly obtained from experimental data, without any fitting procedure. These functions have been developed from the modified generalized potential proposed by Araújo and Ballester. The function for theX 2 Σ + electronic state represents a significant improvement to the previously proposed model. To quantify the accuracy of the potential energy functions, the Lippincont test is used. The novel potential was also compared with the classical Morse potential and with the recently proposed Improved Generalized Pöschl-Teller potential. Furthermore, the main spectroscopic constants and vibrational energy levels are calculated and compared for all potentials. The present results agree excellently with the experiment Rydberg-Klein-Rees (RKR) potentials.

METHODS

The rovibrational energy levels of the proposed diatomic potentials were asserted by solving radial the Schrödinger equation of the nuclear motion with the aid of the LEVEL program.

Reactive collisions between CH+ and O-

Integral cross sections were measured for two reactions occurring in CH+ + O- collisions: the formation of the carbon monoxide cation CO+ via a reactive ionization process and the formation of the (iso)formyl cation HCO+ (HOC+) via the associative ionization process. Both carbon monoxide and formyl cations are present in the interstellar medium, the latter one being quite abundant in dense clouds. Provided the oxygen anion would also be present in the interstellar environment, the large efficiency of the two reactive processes reported here would justify their inclusion in astrochemical models. The whole set of data was obtained by means of a merged-beam setup operating with keV beams.