Three-step laser excitation of the odd-parity 5s5d 3D → 5snf 3F states of cadmium

Abstract

We report new experimental data on the term energies and effective quantum numbers of the highly excited odd parity states of cadmium in the 71 773–72 500 cm−1 energy range. The experiment was performed using three dye lasers simultaneously pumped by the second harmonic (532 nm) of the Nd;YAG laser. The vapor containment and detection system was a thermionic diode ion detector working in a space charge limited mode. The new observations include the 5snf 3F3 (12 ⩽ n ⩽ 52), 5snf 3F4 (13 ⩽ n ⩽ 33) and 5snf 3F2 (12 ⩽ n ⩽ 22) Rydberg series excited from the 5s5d 3D multiplet. A two parameter fit to the transitions energies of the 5snf 3F3 series yields the binding energy of the 5snd 2D2 level as 13 042.178 ± 0.02 cm−1 and consequently the first ionization of cadmium is determined as 72 540.05 ± 0.13 cm−1, which is in good agreement with the previously reported value.