MICROWAVE SPECTRUM AND STRUCTURE OF CIS-1, 2-DIFLUOROETHYLENE OXIDE

Abstract

The microwave spectrum of cis-1, $2-difluoro-^{13}C-ethylene$ oxide $(^{13}CHF^{12}CHFO$) has been assigned in natural abundance using a combination of radio-frequency and microwave-microwave double resonance as well as Stark-modulation techniques. A rigid rotor fit of the spectrum yields the following rotational constants (MHz): $A = 9018.016 \pm 0.063, B = 5147.608 \pm 0.046$, and $C = 3839.510 \pm 0.029.$ Combination of the carbon-13 data with the normal and deuterium isotopic data reported $previously^{1}$ permits a partial determination of the molecular structure. The $r_{s}$ parameters are $r(C-C) = 1.451 \pm 0.002$ {\AA}, $r(C-H) = 1.093 \pm 0.002$ {\AA}, $\angle (CCH) = 126.4 \pm 0.2^\circ$. These structural data will be related to bonding in the ethylene oxide ring system.