Absorption Spectrum of the SiC₂ Radical in the Gaseous Phase

The stellar spectrum of certain N type stars in the blue–green region has been observed in the laboratory in absorption using the flash discharge technique. It has been interpreted as a 1 Π ← 1 Σ transition of the linear Si–C–C molecule. A new vibrational analysis has been proposed, which yields the following fundamental frequencies in cm −1 . [Formula: see text] The 1 Π state shows a small Renner splitting (εω 2 = 3.3 cm −1 ). In addition, 001 and 040 levels are shown to perturb each other due to a Fermi resonance.