Rotational Spectrum of Methylcyanoacetylene A New Millimeter Wave Spectrometer

Abstract

Abstract The ground state rotational spectrum of methylcyanoacetylene, CH 3 CCCN, has been observed between 8 and 90 GHz, yielding precise rotational constants and a determination of the nuclear hyperfine costant eqQ = -4.0 ± 0.2 MHz. The millimeter wave spectra (70 - 90 GHz) were obtained with a newly constructed spectrometer, employing a synthesizer - controlled reflex klystron as source.