Spectre d'Emission de la Molecule PO : Transition C₂Σ⁻–<i>X</i>²Π_r et Nature de l'Etat <i>C</i>′

Abstract

The vibrational and rotational analyses of 27 red degraded subbands of PO in the region 1850–2350 Å, attributed to C–X 2 Π r system, are reported. The bands are photographed with a dispersion of 0.29 Å/mm. We observed three new vibrational levels of the C state. The identification of C as a 2 Σ − state obliged us to reconsider the C–X 2 Π r transition. We concluded that C′ is a 2 Δ state. A table of molecular constants for the C state is given.