Lamb-dip millimeter-wave spectrum, structure and dipole moment of HCCCCF

Abstract

The ground state rotational spectrum of HCCCCF has been observed in the millimeter-wave region using the Lamb-dip technique and very accurate values of the spectroscopic constants have been obtained. Moreover, the observation of the ground state rotational spectra of the four ¹³C monosubstituted isotopomers and of the deuterated species of fluorodiacetylene have enabled the determination of the r₀ and r_s molecular structures. The electric dipole moment of HCCCCF has been determined by observing the Stark spectrum of the J=3â†�2 rotational transition. The equilibrium geometry and the dipole moment have been evaluated using different abinitio methods and comparison between experimental and theoretical results has been made.