Spectroscopic constants and the potential energy curve of the iodine weakly bound 0+g state correlating with the I(2P1/2) + I(2P1/2) dissociation limit

Abstract

The stepwise three-step three-colour I2(D0+u, vD, JD 0+g, v0, J0 B0+u, vB, JB X0+g, vX, JX) laser excitation scheme and rotational as well as rovibrational energy transfer processes in the 0+g state induced by collisions with He and Ar atoms are used for determination of rovibronic level energies of the weakly bound 0+g state correlating with the I(2P1/2) + I(2P1/2) dissociation limit. Dunham coefficients of the state, Yi0 (i = 0–3), Yi1 (i = 0–3) and Y02 for the = 0–16 and ≈ 14–135 ranges as well as the dissociation energy of the state, De, and equilibrium I–I distance of the state, Re, are determined. The potential energy curve of the state constructed using these constants is also reported.