Microwave Spectrum, Dipole Moment, and Ring-Puckering Vibration of Vinylene Carbonate

Abstract

The microwave spectrum of vinylene carbonate has been studied in the frequency region between 12 000 and 26 500 Mc/sec. Rotational constants and moments of inertia have been derived for the vibrational ground state and for the first three excited states of the ring‐puckering vibrational mode. The molecule is planar, with no barrier at the planar configuration in the ring‐puckering potential function. Measured intensities of the vibrational satellites are fitted well by a purely quadratic potential function. The dipole moment, which lies exclusively along the a axis, is 4.57±0.05 D.