The chlorine nuclear quadrupole coupling tensor in chlorotrifluoroethylene

Abstract

The 273 hyperfine components from 56 rotational transitions of chlorotrifluoroethylene were measured with a Fourier transform microwave spectrometer. A global least-squares fit was made to the rotational constants, quartic distortion constants, and 35Cl quadrupole coupling constants; the RMS deviation of the fit was 1.6 kHz. It is shown that such high-resolution measurements enable χ ab to be determined without the near degeneracies usually necessary with less precise data. The principle tensor quadrupole coupling constants are xχ zz = −77.46(10), x xx = 38.85(10), and χ yy = x cc = 38.614(3) MHz. The values are comparable to other vinyl chlorides, removing some anomalies from previous studies.