The microwave spectrum of NiH

Abstract
Numerous microwave transitions between the Λ-doubling components of vibrational levels in the X 2Δ3/2 (v = 0) state of NiH in the gas phase have been measured using the technique of microwave-optical double resonance (MODR) spectroscopy. An effective experimental method for the simultaneous introduction of low-frequency microwave radiation and optical laser radiation into a flowing reaction chamber has been demonstrated. Some Λ-doubling and magnetic hyperfine parameters were obtained from a least squares fit of an effective hamiltonian model to the observed transition frequencies. The spectroscopic parameters are interpreted in terms of the proposed electronic wavefunctions and state distribution.