High-Resolution Laser Spectroscopy of the A3Pi1u <-- X1Sigmag+ System of I2 with a Titanium:Sapphire Ring Laser

The Doppler-limited absorption spectrum of the vibrotational lines in the A3Pi1u <-- X1Sigmag+ system of I2 was measured in the region from 11,200 to 12,450 cm-1 using a Ti:sapphire ring laser. The Q-branch lines of J = 10 to 100 belonging to the v' <-- v" = (26' approximately 45') <-- 0", (19' approximately 45') <-- 1", (16' approximately 45') <-- 2", (16' approximately 42') <-- 3", and (22' approximately 31') <-- 4" progressions were assigned. The hyperfine splittings were observed at the vibrational states around the near-dissociation limit. The unperturbed line positions were obtained by first order approximation for the high-J rotational state. The values of nuQ0, Bvf' - Bv", Dvf' - Dv", and Hv' - Hv" were determined using a least-squares fitting procedure. The spectroscopic constants of Tv', Bvf', Dvf', and Hvf' of v' = 16 approximately 45 were calculated with the aid of the Dunham expansion parameters of the X state and were compared with those reported by D. R. T. Appadoo et al. (J. Chem. Phys. 104(3), 903 (1996)). Copyright 1997Academic Press