Molecular beam electric resonance study of the ground and excited states of cyanoacetylene

Cyanoacetylene was studied using molecular beam electric resonance spectroscopy. Ground state results are μ=3.731 72 D, eQq=−4319.24 kHz, CN=0.976 kHz. Zero field spectra were observed for the three singly excited bending modes and Stark data were taken for the lower energy of two of these three states. Excited state results include ν7; μ=3.7225 D, eQqaa=−4302.0 kHz, eQ(qbb−qcc)=−28.8 kHz, CN(J=2)=1.47 kHz; ν6; μ=3.7263 D, eQqaa=−4369.7 kHz, eQ(qbb−qcc)=177.1 kHz, CB(J=2)=1.30 kHz; ν5; eQqaa=−4325.7, eQ(qbb−qcc)=96.8 kHz, CN(J=2)=1.33 kHz. l-doubling constants were also obtained for the degenerate vibrations.