Extensive ro-vibrational analysis of deuterated-cyanoacetylene (DC$_3$N)
  from millimeter-wavelengths to the infrared domain
  Cyanoacetylene, the simplest cyanopolyyne, is an abundant interstellar
molecule commonly observed in a vast variety of astronomical sources. Despite
its importance as a potential tracer of the evolution of star-forming
processes, the deuterated form of cyanoacetylene is less observed and less
studied in the laboratory than the main isotopologue. Here, we report the most
extensive spectroscopic characterization of DC$_3$N to date, from the
millimeter domain to the infrared region. Rotational and ro-vibrational spectra
have been recorded using millimeter-wave frequency-modulation and
Fourier-transform infrared spectrometers, respectively. All the vibrational
states with energy up to 1015 cm$^{-1}$ have been analyzed in a combined fit,
where the effects due to anharmonic resonances have been adequately accounted
for. The analysis contains over 6500 distinct transition frequencies, from
which all the vibrational energies have been determined with good precision for
many fundamental, overtone, and combination states. This work provides a
comprehensive line catalog for astronomical observations of DC$_3$N
