The far-infrared Laser Magnetic Resonance Spectrum of the OH radical

Abstract

The far-infrared Laser Magnetic Resonance (LMR) Spectrum of the OH radical in the v = 0 level of the X 2Π state has been studied in detail. All transitions that are accessible with currently available laser lines have been recorded. The measurements have been analyzed and subjected to a single least-squares fit using an effective Hamiltonian. The data provide primary information on the rotational and fine-structure intervals between the lowest rotational levels and the parameter values determined in the fit are A ̃ 0 = −4168.63913(78) GHz , γ ̃ 0 = −3.57488(49) GHz , B 0 = 555.66097(11) GHz, D 0 = 0.0571785(86) GHz.