MEASUREMENT OF MOLECULAR G VALUES IN H2O AND D2O AND HYPERFINE STRUCTURE IN H2O

Individual components of the Zeeman transitions in the rotational spectrum of H2O and D2O were resolved in fields of 25-30 kG. This allowed determination of the g values with greater accuracy than previous measurements. The g values obtained for H2O were g(523) =0.6959±0.001 and g(616) =0.6565± 0.001. The g values obtained for D2O were gaa=0.3233±0.001, g cc= 0.3580±0.001, and gcc=0.3226±0.001. Analysis of the combined results indicates that the g values for H2O are positive and that the values are gaa=0.6650±0.002, g bb= 0.7145±0.002, and gcc=0.o465±0.002. Hyperfine structure on the 616-523 transition in H 2O was observed in a maser spectrometer, and the spin-rotation and spin-spin coupling constants were obtained. The measured value of the rotational transition frequency was 22 235 079.85±0.05 kHz. The magnetic susceptibility anisotropies and molecular quadrupole moments were determined in H2O.