Observation of the lowest triplet transitions 3Σ+g–3Σ+u in Na2 and K2

Abstract

We report here the observation and definite identification of the lowest triplet transition ³Σ⁺_g–³Σ⁺_u in Na₂ and K₂. The identification of these bands is based upon direct comparison of K₂ absorption, thermal emission, and laser‐induced fluorescence, and Na₂ laser‐induced fluorescence, with spectra calculated from recent, accurate, ab initio potential curves. These data also serve as a sensitive check on the accuracy of these potentials.