The Microwave Spectrum of Phosgene

Abstract

The microwave spectra of C¹²O¹⁶Cl³⁵Cl³⁵ and C¹²O¹⁶Cl³⁵Cl³⁷ have been investigated in the region 23 000–28 000 Mc/sec. The analyses of the rotational spectra yield for the phosgene molecule: C–O distance=1.166±0.002A; C–Cl distance=1.746±0.004A; and Cl–C–Cl angle=111.3±0.1°. An analysis of the quadrupole hyperfine structure was made for both isotopic species and the quadrupole coupling constants were obtained for C¹²O¹⁶Cl³⁵Cl³⁵. An attempt is made to explain the large observed value of the field dyadic asymmetry parameter η.