Comparative study of the 2125 AA Cd and 1692 AA Hg absorption bands. Excited-state potentials and oscillator strength determinations

Abstract

The 1692 AA mercury and 2125 AA cadmium absorption bands are analysed. The temperature dependence of the profiles is studied and interpreted in the framework of the quasistatic theory. The 1692 AA mercury absorption band is attributed to transitions ending at the 1 Sigma +u Rydberg excited-state arising from Hg(71S0)-Hg(61S0). Because the energy curve of the ground state is available, the excited-state potential energy curve is deduced: De=4800+or-50 cm-1 at Re=3.4+or-0.1 AA. The oscillator strength of the transition is derived to be between 3.2 and 3.5 AA. The analysis of the 2125 AA cadmium absorption band shows that this band is the superposition of two non-resolved absorption bands involving transitions ending at the 3 Sigma +u and 1 Sigma +u Rydberg states arising from Cd(63S1)-Cd(51S0) and Cd(61S0)-Cd(51S0) respectively. As the energy curve of the ground state is available, the excited-state potential energy curves are deduced: De(3 Sigma +u)=4910+or-50 cm-1 at Re=3.05+or-0.15 AA and De(1 Sigma +u)=6420+or-50 cm-1 at Re=3.0+or-0.1 AA. The oscillator strengths of the transitions are derived to be between 2.4 and 3.5 AA and between 2.2 and 4 AA respectively.