Continuous wave optically pumped iodine laser: Spectroscopy and long range analysis of the X1Σg+ ground state of I2

Continuous wave oscillation is observed on transitions belonging to the I₂B 0_u⁺-X¹Σ_g⁺ system into highly excited vibrational levels of the ground state. The I₂ laser is optically pumped with a single longitudinal mode argon ion laser oscillating at either 514.5 or 501.7 nm resulting in some 752 assigned laser lines throughout the visible and near infrared. Of these, 44 transitions have 83 ≤ v″ ≤ 96 and are used here to obtain rotational and vibrational constants for levels of X¹Σ_g⁺ near the dissociation limit. A long range analysis applying the theory of LeRoy to the highest observed levels yields C₆ = 1.1 ± 0.1 × 10⁶ cm^?1 Å^?6 and indicates that the last bound vibrational level of X¹Σ_g⁺ has v = 114.