The microwave spectrum of vinyl cyanide

Abstract

The rotational spectrum of the slightly asymmetric top, vinyl cyanide, has been investigated in a microwave spectrograph employing Stark effect modulation and in a direct absorption cell. The rotational constants a=49 076.2 Mc/sec, b=4971.33, and c=4514.05 were computed from the observed frequencies of the J=2→3 transitions. From measurements of the Stark effect, the components of the dipole moment were found to be μa=3.68D, μb= 1.25, μ=3.89. Partial resolution of the hyperfine structure of certain lines gave the value -3.0 Mc/sec for the χaa component of quadrupole coupling.