THE INFRARED SPECTRA AND STRUCTURE OF ETHYLENE $CARBONATE^{\#}$

Abstract

The infrared spectra of ethylene carbonate $(CH_{2}-O-CO-O-CH_{2}$ in the solid, liquid and vapor states and its solutions in water, chloroform, benzene, carbon tetracloride and carbon disulfide have been studied between 3600 and $400 cm^{-1}$, together with the Raman spectrum in aqueous solution. Previous X-ray crystal structure $determination^{1}$ has shown that the five-membered ring of the ethylene carbonate molecule is not planar and has symmetry $C_{2}$ in the crystal. Evidence will be presented from the spectroscopic work that the symmetry of the molecule changes from $C_{2}$ in the solid state to $C_{2{v}}$ in the other states and that the five-membered ring becomes planat. An assignment of all the observed absorption bands will be given in terms of the fundamental vibrations of the molecule.