Heterogeneous and hyperfine interactions between valence states of molecular iodine correlating with the I(2P1/2) + I(2P1/2) dissociation limit

Abstract

Detailed analysis of interactions between all 0 g +, 1u, and 0 u - weakly bound states of iodine molecule correlating with the I(2P1/2) + I(2P1/2) (bb) dissociation limit has been performed. For this purpose, the 0 u - (bb) state has been described using analysis of rotationally resolved excitation spectra of luminescence from the g 0 g - state populated in a three-step three-color perturbation facilitated excitation scheme via the 0 u - state. Energies of 41 rovibrational levels, molecular constants, and potential energy curve have been determined. Energy gaps between closest rovibrational levels of the 0 u - and 0 g +, 1u (bb) states are found to be large, ∼6 cm-1. However, interaction of all three 0 g +, 1u, and 0 u - (bb) states has been observed. It has been found that the 0 u - and 1u electronic states are mixed by heterogeneous interactions, while their mixing with the 0 g + one is due to hyperfine interactions predominantly. Admixture coefficients and electronic matrix elements of the coupling between the 0 g + ∼1u, 0 g + ∼ 0 u -, and 0 u - ∼1u states have been estimated. © 2016 Author(s).