Raman spectra of overheated sulfur vapor

Our thermodynamic study allows to confirm the selective observation with a blue exciting line (457.9 or 476.5 nm) of the resonance Raman spectra of the S₃ molecule. The extinction coefficient of the maximum λ = 395 nm of its absorption spectrum ε = 2100 1 mole⁻¹ cm⁻¹ is quite lower than that previously reported. The resonance Raman spectra of ³²S₃ and ³⁴S₄ may be explained with three normal frequencies and confirm the bent C_2v geometry of this molecule in perfect agreement with the structure of the parent anions, S⁻₃ and S²⁻₃.