Paramagnetic Resonance Absorption in Bromine and Chlorine

The microwave Zeeman spectra of atomic chlorine and bromine have been observed. From measurements on several lines in the spectrum of the 2 P 3 2 ground level, the electronic g -factors are found to be g J (Br) = 1.333921 ± (5 × 10 -6 ) g J (Cl) = 1 333927 5 ± (3 × 10 -6 ). An estimate of relativistic and diamagnetic corrections to the g -factors, based on self-consistent field wave functions, is in satisfactory agreement with the experimental results. A comparison is made with the g -factors of fluorine and iodine.