Table of Contents
Laser Chemistry
Volume 7, Issue 2-4, Pages 79-93

A Spectroscopic Study of the D(0u+) Ion-Pair State of I2 by Optical–Optical Double Resonance

Department of Chemistry, Tokyo Institute of Technology, Ohokayama, Meguro, Tokyo 152, Japan

Copyright © 1987 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The D(0u+) ion-pair state of I2 has been analyzed by the optical–optical double resonance (OODR) technique. In a stepwise three-photon excitation scheme, D(0u+)–B3Π(0u+)–X1Σg+, the D(0u+) state appeared in the OODR spectrum as the vibrational progressions consisting of O, Q and S branches in accord with the rotational selection rule of ΔJ = 0 and ±2 for the coherent two-photon transition from the B3Π(0u+) state. The D(0u+)–X1Σg+ fluorescence was resolved to determine the absolute vibrational numbering of the D(0u+) state. We derived Dunham parameters effective for ν = 0 through ν = 124 which were used to construct a Rydberg–Klein–Rees (RKR) potential curve.