Abstract
The infrared spectra of gaseous ethylene oxide and ethylene oxide‐d4 in the range 375—3800 cm—1 and the Raman spectra of the liquids have been determined. With the help of the infrared band contours and the product rule, a complete vibrational assignment has been made for both molecules. The assignments correlate well with those of cyclopropane and cyclopropane‐d6.