Raman spectra of asymmetric top molecules. Part 1.—The pure rotational spectrum of ethylene

Abstract

From an investigation of the rotational Raman spectrum of ethylene, single transitions were assigned which allowed the determination of all three rotational constants: A₀= 4.866₆± 0.004₀ cm^–1, B₀= 1.0007₆± 0.0001₃ cm^–1, C₀= 0.828 4₈± 0.000 1₆ cm^–1. The spectrum was also computer simulated using an asymmetric rotor programme and, from a comparison of observed and calculated spectra, values were determined for the principal polarisabilities of the molecule: α_zz= 5.40 ų, α_xx= 3.86 ų, α_yy= 3.40 ų.