Observations on the absorption and fluorescence spectra of gaseous Te2

Abstract

Detailed rotational analysis of bands of the A 0⁺_u–X 0⁺_g and B 0⁺_u–X 0⁺_g systems of ¹²⁸Te₂, observed in absorption, has been extended to low values of v′ and high values of v″. This has led to the identification of several resonance fluorescence series excited by lines of the Ar⁺ laser. Franck-Condon factors have been calculated from RKR potential curves for both systems A, B—X, and they are confirmed experimentally by the observed relative intensities in the fluorescence series. The level v= 0 in B 0⁺_u is perturbed, and the fluorescence spectra are found to contain weak series, v′= 0 B 0⁺_u to v″X 1 ⁺_g, whose analysis leads to a determination of the ground state X 1⁺_g—X 1⁺_g 0⁺_g separation: the most probable value is found to be ⩽ 2230 cm^–1 at the potential energy minima.