HYPERFINE-STRUCTURE OF THE R(98), 58-1 LINE OF I-127(2) AT 514.5 NM

The hfs components of a weak rotational line of 127I2, assigned as the R(98) line of the 58→1 band, are resolved by saturated intermodulated fluorescence and a third-derivative technique using a single-mode Ar+-laser at 514.5 nm. The spacings between different hfs components are measured by a heterodyne technique with an accuracy of 30 kHz. The differences between the upper and lower coupling constants obtained by a fit giving a standard deviation of 15.2 kHz, are: δeqQ = 1880.198 ± 0.09 MHz; δC = 829.20 ± 0.04 kHz for the spin-rotation constant; δD = -501.9 ± 3.5 kHz for the scalar spin-spin and δA = 356.8 ± 1.1 kHz for the tensor spin-spin interaction. The results are compared with data for other vibrational transitions. © 1979.