Terahertz spectroscopy and global analysis of the rotational spectrum of doubly deuterated Amidogen radical ND${}_2$

Abstract

The deuteration mechanism of molecules in the interstellar medium (ISM) is still being debated. Observations of deuterium-bearing species in several astronomical sources represent a powerful tool to improve our understanding of the interstellar chemistry. The doubly deuterated form of the astrophysically interesting Amidogen radical could be a target of detection in space. In this work, the rotational spectrum of the ND${}_2$ radical in its ground vibrational and electronic $X^2{B}_1$ states has been investigated between 588 and 1131 GHz using a frequency modulation millimeter/submillimeter-wave spectrometer. The ND${}_2$ has been produced in a free-space glass absorption cell by discharging a mixture of ND${}_3$ and Ar. Sixty-four new transition frequencies involving $J$ values from 2 to 5 and $K_a$ values from 0 to 4 have been measured. A global analysis including all the previous field-free pure rotational data has been performed, allowing for a more precise determination of a very large number of spectroscopic parameters. Accurate predictions of rotational transition frequencies of ND${}_2$ are now available from a few GHz up to several THz.

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Cited by in corpus (5)

• The rotational spectrum of ${}^{15}$ND. Isotopic-independent Dunham-type analysis of the imidogen radical
• First detection of NHD and ND${}_2$ in the interstellar medium
• The Sub-millimeter Rotational Spectrum of Ethylene Glycol up to 890 GHz and Application to ALMA Band 10 Spectral Line Data of NGC 6334I
• Deuterium fractionation of nitrogen hydrides: detections of NHD and ND${}_2$
• Submillimetre and far-infrared spectroscopy of monodeuterated amidogen radical (NHD): improved rest-frequencies for astrophysical observations