Hyperfine interactions in homonuclear diatomic molecules and u-g perturbations. II. Experiments on I2

J. P. Pique , F. Hartmann , S. Churassy , R. Bacis

The iodine B 0+u state is studied near its dissociation limit using sub-Doppler high resolution techniques. The recording of more than 10 000 hyperfine lines allows a systematic analysis of the hyperfine structure. All the observed features can be accounted for by the calculation of the interactions of the B state with the other electronic states sharing the same dissociation limit. Three different situations are encountered : weak perturbation situations treated in the second-order approximation of the Broyer, Vigué, Lehmann theory, superhyperfine structures observed in several band heads, and strong perturbation cases (vibrational levels ν' = 76, 77 and 78). This last situation has required the utilization of the full exact interaction matrix of B 0+u with a 1 g state, leading to the first direct evidence of a u-g symmetry breaking in a homonuclear diatomic molecule.

Mots clés: iodine; molecular beams; molecular dissociation; molecular hyperfine structure

Domaines: Articles anciens

J. P. Pique, F. Hartmann, S. Churassy, R. Bacis. Hyperfine interactions in homonuclear diatomic molecules and u-g perturbations. II. Experiments on I2. Journal de Physique, 1986, 47 (11), pp.1917-1929. ⟨10.1051/jphys:0198600470110191700⟩. ⟨jpa-00210388⟩