Vibrational Spectra of CF2 = CHD and CF2 = CD2

Abstract

A method has been devised to prepare CF₂ = CD₂ and CF₂ = CHD. The infrared spectra of the gaseous compounds and the Raman spectra of the liquids have been determined. The observed frequencies have been assigned to the fundamental modes of vibration and to overtones and combinations. The torsional frequency has been estimated as ca 720 and ca 520 cm^—1 in CF₂ = CH₂ and CF₂ = CD₂, respectively. The overtone of the torsional frequency interacts with the CH₂ or the CD₂ deformation fundamental and this is the cause of the anomalous results with the product rule.