Deuterium hyperfine structure measurements and theory for CD3Br

Hyperfine structure on the J = 1→0, F1 = 3/2 transitions in CH3 79Br, CH3 81Br, and CD3 79Br was measured with one-cavity and two-cavity beam maser spectrometers. The resolution for the measurements was approximately 2 kHz and most hyperfine structure components were completely resolved. Deuterium quadrupole coupling eQqzz = 178.5±3 khz along the C–D bond and other parameters were obtained. In the theory section, formulas for the hyperfine interaction strengths with three equivalent spins are presented and reviewed. Deuterium quadrupole coupling in other C–D bond systems is discussed.