Spin-orbit relaxation of Te(53 P 1) and Te(53 P 0)

Abstract

Spin-orbit relaxation of Te(5³P₁) and Te(5³P₀) by the gases H₂, D₂, O₂, He, Ar and Xe, has been studied using time resolved atomic absorption spectroscopy in the ultra-violet. The absolute rate for relaxation by H₂ was determined as k_{H2 =(1.03 ± 0.15)× 10^–11 cm³ molecule^–1 s^–1; cross-section σH2 = 0.58 × 10^–16 cm². Relaxation by D2 is three orders of magnitude less efficient than by H2, and represents the largest quantifiable isotope effect known. The noble gases He, Ar and Xe were found to be relatively inefficient having cross-sections less than 10^–19 cm² for relaxation. Quenching by oxygen was also found to be inefficient (kO2 =(1.28 ± 0.55)× 10^–14 cm³ molecule^–1 s^–1; σO2 = 2.6 × 10^–19 cm²). The results are discussed within the context of resonant energy transfer processes, and the role of predissociation of the potential energy surfaces is considered.}