Free-jet laser-induced fluorescence spectroscopy of NbN: Observation of a new 3Π state

Abstract

We report laser-induced fluorescence spectroscopy of the jet-cooled NbN molecule in the 20,300–20,800cm−1 region. A new 3Π state with spin–orbit components, Π0±3, 3Π1, and 3Π2 respectively at term energies 20,756.32, 20,900.1 and 21,240.3cm−1 has been observed. The radiative lifetime and rotational constant data suggest that the 3Π1 spin–orbit component is mixed and is responsible for the asymmetric spin–orbit splitting of the 3Π state.