Abstract
Paramagnetic resonance absorption at 3-cm wavelength has been observed in the products of an electric discharge in low-pressure O and O vapor. The spectra are of the electric dipole type, and arise from -type doubling transitions in low-lying rotational levels of the free H and D radicals. The theory of the Zeeman effect in levels of light diatomic radicals is extended to the general intermediate coupling case, and is used for a detailed analysis of the observed spectra. Numerical results of this analysis include molecular factors precise to within 3 parts in , and magnitudes of the -type doubling intervals in several low rotational levels. The measured factors are compared with theory, including small corrections for molecular rotation, the anomalous spin magnetic moment of the electron, and estimated relativistic effects. This comparison yields the value 0.67±0.01 for the molecular matrix element (), and also brings to light serious discrepancies between the present experimental results and earlier measurements of the -type doubling in OH and OD. The paramagnetic resonance spectra also exhibit hyperfine structure, from which are derived molecular constants that describe the distribution of unpaired electrons about the H or D nucleus.
- Received 7 November 1960
DOI:https://doi.org/10.1103/PhysRev.122.114
©1961 American Physical Society